Region | Title | System | Version | Edition | Languages | Serial | Status |
| Oro Negro: Juego de Guerra y Estrategia | PC | | Covermount | | | |
| Oesterreichische Nationalbibliothek: Multimediale Enzyklopaedie auf 3 CD-i's (Disc 1) (Prunksaal/Impressionen) | CDI | | Original | | 0103313 | |
| Oesterreichische Nationalbibliothek: Multimediale Enzyklopaedie auf 3 CD-i's (Disc 2) (Sammlungen) | CDI | | Original | | 0103313 | |
| Oesterreichische Nationalbibliothek: Multimediale Enzyklopaedie auf 3 CD-i's (Disc 3) (Apokalypse) | CDI | | Original | | 0103313 | |
| Osterreichs Werbepreise: Vier Highlights | CDI | | Original | | | |
| Oct 15 2002 | PC | | Press Kit | | | |
| Over 350 Jigsaw Puzzles | PC | | Original | | 012163 | |
| Over 350 Solitaire Games | PC | | Original | | | |
| Ouro e Glória: O Caminho para El Dorado | PC | | Original | | 906.02.0 | |
| Outlaws: Cidade Sem Lei (Disc 1) | PC | 2.0 | Original | | 0806.05.0 | |
| Outlaws: Cidade Sem Lei (Disc 2) | PC | 2.0 | Original | | 0806.06.0 | |
| Ollo en de Reuzentomaat | PC | | CD-ROM Topper | | | |
| Oblivious Garden: Carmina Burana (Disc 2) (Music Disc) | PC | | Standard Edition | | | |
| ObsCure (Disc 1) 惊悚空间 | PC | 1.0 | Original | | | |
| ObsCure (Disc 2) 惊悚空间 | PC | 1.0 | Original | | | |
| ObsCure (Disc 3) 惊悚空间 | PC | 1.0 | Original | | | |
| ObsCure (Disc 4) 惊悚空间 | PC | 1.0 | Original | | | |
| Oni 奥妮 | PC | 1.7 | Original | | | |
| Omar Sharif Bridge | PC | 1.0 | Original | | | |
| Operation | PC | | General Mills | | | |
| Over 1000 Games: The Complete Encyclopedia of Games: Volume II (Disc 1) Over 1000 Games Volume 2 | PC | | Original | | | |
| Over 1000 Games: The Complete Encyclopedia of Games: Volume II (Disc 2) Over 1000 Games Volume 2 | PC | | Original | | | |
| Over 200 Programs for Windows STG Computers LTD Windows Extra CD-ROM | PC | | Original | | | |
| Operation Flashpoint: Gold Upgrade Operace Flashpoint: Gold Upgrade | PC | | Original | | | |
| O.D.T. | PSX | | Original | | SLES-01391 | |
| O.D.T. | PC | | Dice | | DCG 005509 | |
| O.D.T. | PC | | Original | | | |
| Ocean Commander | PS2 | 1.01 | Original | | SLES-55047 | |
| Ocean/Infogrames Show Case December 1997 | PC | | | | | |
| Oddballz: Your Wacky Computer Petz | PC | 1.0 | Original | | CS090370 | |
| Oddworld: Abe's Exoddus (Play Disc) | PC | 2.0 | Budget, Covermount | | MMICDR 5280 | |
| Oddworld: Abe's Exoddus (Install Disc) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (Play Disc) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (Disc 1) | PSX | | Original, Platinum | | SLES-01480 … | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original, Platinum | | SLES-11480 … | |
| Oddworld: Abe's Exoddus + Duke Nukem: Time To Kill + B-Movie | PSX | | Demo | | SLED-01608 | |
| Oddworld: Abe's Exoddus: UK Packaging | MAC | | Art Assets | | | |
| Oddworld: Abe's Exoddus: US Manual | MAC | | Art Assets | | | |
| Oddworld: Abe's Oddysee | PSX | | Demo | | SLED-00725 | |
| Oddworld: Abe's Oddysee | PSX | | Original, Platinum, Best of Infogrames: Value Series, Best of Infogrames: Adventure | | SLES-00664 … | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Original | | IB2G-ODD5 | |
| Odyssey: The Search for Ulysses (Disc 1) | PC | | Original | | ODY-ENCD1 | |
| Odyssey: The Search for Ulysses (Disc 2) | PC | | Original | | ODY-ENCD2 | |
| Of Light and Darkness: The Prophecy (Disc 1) | PC | | Original | | CD-W95-166-E | |
| Of Light and Darkness: The Prophecy (Disc 2) | PC | | Original | | CD-W95-166-E | |
| Of Light and Darkness: The Prophecy (Disc 3) | PC | | Original | | CD-W95-166-E | |
| Off Road | PS2 | 1.01 | Original | | SLES-55032 | |
| Off-Road: Wide Open Test Drive Off-Road: Wide Open | PS2 | 1.00 | Original | | SLES-50232 | |
| Off-World Interceptor Extreme | PSX | | Original | | SLES-00047 | |
| Off-World Interceptor Extreme | SS | 1.000 | Original | | T-15908H-50 | |
| Offensive | PC | | Original | | | |
| Official Formula 1 Racing | PC | | Original | | | |
| Official PlayStation 2 Magazine Demo 3 | PS2 | 1.00 | | | SCED-50067 | |
| Official PlayStation 2 Magazine Demo 5 | PS2 | 1.00 | | | SCED-50140 | |
| Official PlayStation Magazine Best Games Ever 2000 | PSX | | | | SCED-03375 | |
| Official PlayStation Magazine Platinum Special Demo Official UK PlayStation Magazine Platinum Special | PSX | | | | SCED-02122 | |
| Offroad Off-Road Redneck Racing | PC | | Original | | OFFPCCDML | |
| Offroad Extreme! | PS2 | 1.01 | Original | | SLES-52751 | |
| Offroad Extreme! Special Edition | PC | | Original | | | |
| Offroad Extreme! Special Edition | PS2 | 1.00 | Original | | SLES-54109 | |
| Oil Platform Simulator | PC | 1.0 | Original | | | |
| Okano Software Classics: Volume 2 | PC | | Original | | | |
| Olympic Games | 3DO | | Bundled with Magazine (Demo) | | | |
| Olympic Games Olympic Games: Atlanta 1996 | PSX | | Original | | SLES-00110 | |
| Olympic Games: Atlanta 1996 | PC | | Original | | | |
| Olympic Soccer | PSX | | Original | | SLES-00113 | |
| Olympic Soccer | SS | 2.000 | Original | | T-7904H-09, T-7904H-50 | |
| Omega Assault | PSX | | Original | | SLES-04051 | |
| Omega Boost | PSX | | Original | | SCES-02120 | |
| The Omega Stone: Secrets of the Ancients (Disc 1) | PC | | Original | | OMSTENCD1 | |
| The Omega Stone: Secrets of the Ancients (Disc 2) | PC | | Original | | OMSTENCD2 | |
| The Omega Stone: Secrets of the Ancients (Disc 3) | PC | | Original | | OMSTENCD3 | |
| The Omega Stone: Secrets of the Ancients (Disc 4) | PC | | Original | | OMSTENCD4 | |
| Omikron: The Nomad Soul | PC | | Promo | | | |
| On the Ball: League Edition | PC | 1.0 | Original | | | |
| On the Ball: World Cup Edition | PC | 1.00 | Original | | | |
| One | PSX | | Original | | SLES-00944 | |
| One Must Fall 2097 One Must Fall 2097 CD-ROM | PC | 1.1 | ROMWARE | | ROM 10017 | |
| One Must Fall 2097 | PC | 2.1 | The Smile Edition | | CDR3016 | |
| One Must Fall: Battlegrounds | PC | 2090 | Original | | | |
| One Piece Mansion | PSX | | Original | | SLES-03723 | |
| One Step Beyond | PC | | Hit Squad: Regenerator | | | |
| OnEscapee | ACD | | Original | | | |
| Oni | PC | 1.0 | Original | | | |
| Oni | PS2 | 1.02 | Original, Platinum | | SLES-50134 … | |
| Onside Complete Soccer | PSX | | Original | | SLES-00079 | |
| Onside Complete Soccer | PSX | Rev 1 | Original | | SLES-00079 | |
| Opel Corsa '97 | PHOTO-CD | | Original | | | |
| Opel IAA '97 | PHOTO-CD | | Original | | | |
| Opel IAA '99 (Disc 1) (Model Range) | PHOTO-CD | | Original | | | |
| Opel IAA '99 (Disc 2) (Opel Highlights) | PHOTO-CD | | Original | | | |
| Opel Vectra '99 | PHOTO-CD | | Original | | | |
| Open Season (Disc 1) | PC | 1.00 | Original | | 5004904-CD 1 | |
| Operation Air Assault | PS2 | 1.01 | Original | | SLES-52572 | |
| Operation Air Assault 2 | PS2 | 1.01 | Original | | SLES-54804 | |
| Operation Flashpoint: Cold War Crisis | PC | 1.0 | Original | | MOPFCDEU00 | |
| Operation Flashpoint: Cold War Crisis | PC | 1.0 | Original, Gold Edition | | MOPFCDEU00 | |
| Operation Flashpoint: Cold War Crisis | PC | 1.46 | Sold Out Software | | | |
| Operation Flashpoint: Cold War Crisis | PC | 1.46 | Sold Out Software | | | |
| Operation Flashpoint: Resistance | PC | 1.75 | Original | | MOFRCDEU00 | |
| Operation WinBack | PS2 | 1.10 | Original | | SLES-50155 | |
| Operation: Surgery Has Never Been so Silly! | PC | | Replay Kids | | OPERPCREGB/A | |
| Operation: Surgery Has Never Been so Silly! | PC | | Sold Out Software | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | FXX08903223D1 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | S0026178 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (Xplosiv) | | EI-1685-1 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.0 | Original | | FXX08903223D2 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.004 | Game of the Year Edition (Xplosiv) | | EI-1685-2 | |
| OPSM Best Ever Ever Games Demo | PSX | | Demo | | SCED-02851 | |
| OPSM Best Racing Game Ever | PSX | | | | SCED-02492 | |
| Origami | CDI | | Original | | 810 0041 | |
| Orion's Puzzle Collection | DC | 1.000 | Unlicensed | | | |
| Oscar | PC | | Golden Zone | | | |
| Oscar | PC | | Original | | | |
| Othello | CDI | | Original | | 810 0163 | |
| Othello CD-ROM | PC | | Original | | | |
| Outcast (Disc 1) | PC | | Original | | OUTCAPC52G/A1 | |
| Outcast (Disc 2) | PC | | Original | | OUTCAPC52G/A2 | |
| Outlaw Golf | PC | | Original | | RM-OUTGOLF-UK | |
| Outlaw Racers | PC | | Sold Out Software | | | |
| Outlaws (Disc 1) | PC | 1.0 | Original | | 9511830 | |
| Outlaws (Disc 1) | PC | 2.0 | LucasArts Classics | | 3000009.101.UK | |
| Outlaws (Disc 2) | PC | 1.0 | Original | | 9511831 | |
| Outlaws (Disc 2) | PC | 2.0 | LucasArts Classics | | 3000009.102.UK | |
| Outlive | PC | 1.01 | Original | | | |
| Outpost | PC | | Original | | S390021012ZZ2 | |
| Outpost | PC | | SierraOriginals | | S4941220Z12Z2 | |
| Outpost | PC | | Original | | S 390121012ZZZ | |
| Outpost | PC | 1.51 | Schweinepreise | | S390122CZ12ZZ | |
| Outpost 2: Divided Destiny | PC | | SierraOriginals | | | |
| Outpost 2: Divided Destiny | PC | 1.0 | Original | | S0011246 | |
| Outrage | PC | | Original | | | |
| Outtrigger | DC | 1.001 | Original | | MK-51102-50 | |
| Outwars (Disc 1) | PC | 1.0 | Original | | 0298 Part No. X03-63527 | |
| Outwars (Disc 2) | PC | 1.0 | Original | | 0298 Part No. X03-57509 | |
| OverBlood | PSX | | Original | | SLES-00768 | |
| OverBlood 2 (Disc 1) | PSX | | Original | | SLES-01879 | |
| OverBlood 2 (Disc 1) | PSX | Rev 1 | Original | | SLES-01879 … | |
| OverBlood 2 (Disc 2) | PSX | | Original | | SLES-11879 | |
| OverBlood 2 (Disc 2) | PSX | Rev 1 | Original | | SLES-11879 … | |
| Overboard! | PC | | Original | | | |
| Overboard! | PC | | Dice | | DCG 005752, DMM 005776 | |
| Overboard! | PSX | | Original, 1998 4 PlayStation Multi Pack | | SLES-00865 | |
| Overboard! | PC | | Dice | | DCG 005752, DMM 005776 | |
| OverKill | PC | | ROMWARE | | ROM 10 007 | |
| Overkill & Lunar-C | CD32 | | Original | | /DP130002 | |
| The Oxfordshire Golf Club | PC | | Original | | EAE05101006D | |
| Open Season (Disc 2) | PC | 1.00 | Original | | 5004904-CD 2 | |
| Open Season (Disc 3) | PC | 1.00 | Original | | 5004904-CD 3 | |
| Obliterate | PS2 | 1.01 | Original | | SLES-53355 … | |
| Official PlayStation 2 Magazine Demo 1 | PS2 | 1.00 | | | SCED-50065 | |
| Official PlayStation 2 Magazine Demo 2 | PS2 | 1.00 | | | SCED-50066 | |
| OPSM Best PS One Games Ever Official Australian PlayStation Magazine Demo 44 | PSX | | | | SCED-03239 | |
| O.D.T. | PSX | | Original | | SLES-01409 | |
| O.D.T. | PSX | | Demo | | SLED-01574 | |
| Objectif Transparence | CDI | | Original | | RP IND 4 94 | |
| Objectif Transparence | CDI | | Original | | RP IND 4 94 | |
| Oddworld: Abe's Exoddus + Duke Nukem: Time to Kill + Duke Nukem: 3D | PSX | | | | SLED-01655 | |
| Oddworld: L'Exode d'Abe (Disc 1) | PSX | | Original | | SLES-01502 | |
| Oddworld: L'Exode d'Abe (Disc 2) | PSX | | Original | | SLES-11502 | |
| Oddworld: L'Odyssée d'Abe | PSX | | Original, Best of Infogrames | | SLES-00838 … | |
| Oddworld: L'Odyssée d'Abe | PC | | Original | | IB2G-ODDF5 | |
| One | PSX | | Demo | | SLED-01170 | |
| One Must Fall 2097 | PC | | Demo: JukeBox Collection | | | |
| Oni | PS2 | 1.02 | Original | | SLES-50176 | |
| Online G@mer n. 5: Juin/Juillet 2001 (Disc 1) | PC | | | | | |
| L'Open de Palm Springs | CDI | | Original, For Demonstration Only | | 812 0002 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | JCPL11, S0026695 | |
| Original War (Disc 1) | PC | | Original | | | |
| Original War (Disc 2) | PC | | Original | | | |
| Les Ours Berenstain: Comme des Grands | CDI | 1.05 | | | 812 0063 | |
| Outcast (Disc 1) | PC | | Original | | OUTCAPC52F/A1 | |
| Outlaws (Disc 1) | PC | | Original | | | |
| Outlaws (Disc 1) | PC | | M6 Multimedia | | M6IMM6 | |
| Outlaws (Disc 1) | PC | 2.0 | Collection LucasArts | | | |
| Outlaws (Disc 2) | PC | | Original | | | |
| Outlaws (Disc 2) | PC | | M6 Multimedia | | M6IMM6 | |
| Outlaws (Disc 2) | PC | 2.0 | Collection LucasArts | | | |
| OverBlood | PSX | | Original | | SLES-00769 | |
| O.D.T. | PSX | | Demo | | SLED-01575 | |
| O.D.T. | PC | | Original | | | |
| O.D.T. | PSX | | Original | | SLES-01410 | |
| Obsidian (Disc 1) | PC | | Original | | | |
| Obsidian (Disc 2) | PC | | Original | | | |
| Obsidian (Disc 3) | PC | | Original | | | |
| Obsidian (Disc 4) | PC | | Original | | | |
| Obsidian (Disc 5) | PC | | Original | | | |
| Ocean Jewels | PC | | Red Rocks | | | |
| Oddworld: Abe's Exoddus (CD Installieren) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (CD Abspielen) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (Disc 1) | PSX | | Original | | SLES-01503 | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original | | SLES-11503 | |
| Oddworld: Abe's Oddysee | PSX | | Platinum | | SLES-00839 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Original | | IB2G-ODDG5 | |
| Odyssee: Auf der Suche nach Odysseus (Disc 1) | PC | | Original | | ODY-GERCD1 | |
| Odyssee: Auf der Suche nach Odysseus (Disc 2) | PC | | Original | | ODY-GERCD2 | |
| Of Light and Darkness: The Prophecy (Disc 1) | PC | | Original | | | |
| Of Light and Darkness: The Prophecy (Disc 2) | PC | | Original | | | |
| Of Light and Darkness: The Prophecy (Disc 3) | PC | | Original | | | |
| Off Limits: Cassiopeia | PC | | ROMWARE | | ROM 10100 | |
| Off Limits: Mizar | PC | | ROMWARE | | ROM 10120 | |
| Offroad Off-Road Redneck Racing | PC | | Original | | ECD 000592K | |
| Ogallala: Das Kartenspiel für PC | PC | | Original | | ECD000799D 00031111-001 | |
| Oil Tycoon | PC | 1.0 | Original | | | |
| Oil Tycoon 2 | PC | | Original | | | |
| OIO: The Game: Enlarged | PC | | F*ckn' Best of Independent Games: Collection Vol. 1 | | | |
| Oktoberfest Wiesn-Gaudi | PC | 1.0 | Original | | | |
| Oldtimer | PHOTO-CD | | Original | | 813 0067 | |
| Oldtimer | ACD | | Original | | | |
| Oldtimer: Erlebte Geschichte Teil II | PC | | Original | | | |
| Olympic Soccer | PC | | Kixx | | | |
| Olympic Soccer | SS | 2.000 | Original | | T-07904H-18 | |
| One Step Ahead | CDI | | | | Demo 10.05.94 | |
| Oni | PS2 | 1.02 | Original | | SLES-50177 | |
| Onkel Alberts geheimnisvolles Notizbuch | PC | | Original | | | |
| Open Season (Disc 1) | PC | | Original | | 5004905-CD 1 | |
| Open Season (Disc 2) | PC | | Original | | 5004905-CD 2 | |
| Open Season (Disc 3) | PC | | Original | | 5004905-CD 3 | |
| Opera Fatal | PC | | Tandem | | 1444 | |
| Opera Fatal | PC | | Original | | | |
| Operation Barbarossa: The Struggle for Russia | PC | | Original | | | |
| Operation Mittelmeer | PC | | Original | | | |
| The Operational Art of War II: 1956-2000 The Operational Art of War II: Bewaffnete Konflikten | PC | | Original | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition | | S0025036 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.0 | Original | | FXX08903223D2 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.004 | Game of the Year Edition | | S0025037 | |
| Die Original Moorhuhn Jagd | PC | | Best of Moorhuhn | | | |
| Orion Burger | PC | | Original | | | |
| Orion Burger | PC | | Gold Games 2 (CD 11) | | SPI 046 | |
| Orion Burger | PC | | Abenteuer Doppelpack: Premier Collection | | MOBRLPGE72 | |
| Oscar der Ballonfahrer und die Geheimnisse des Waldes | PC | | | | | |
| Osterspiele-Box Oster Spielebox | PC | | Original | | | |
| Othello | PC | | Original | | | |
| Otto Bock: Orthopädische Industrie: Neuheiten Vol. 2: Stand Januar 1997 | CDI | | Original | | | |
| Otto's Ottifanten | PC | | Original | | | |
| Our Worst Fears: Die Blumen des Todes | PC | | Original | | | |
| Outbreaker | PC | | Original | | | |
| Outcast (Disc 1) | PC | | Play the Games Vol. 3 | | | |
| Outcast (Disc 1) | PC | | Limitierte Sonderausgabe | | OUTCAPC520/A1 | |
| Outcast (Disc 2) | PC | | Limitierte Sonderausgabe | | OUTCAPC520/A2 | |
| Outcast (Disc 2) | PC | | Play the Games Vol. 3 | | | |
| Outcast (Disc 3) | PC | | Limitierte Sonderausgabe | | OUTCAPC520/A3 | |
| Outer Ridge | PC | 1.0 | Original | | SPI004 | |
| The Outforce | PC | 1.0.0.0 | Original | | | |
| Outlaws (Disc 1) | PC | 1.0 | Original | | | |
| Outlaws (Disc 1) | PC | 1.1 | Rerelease | | | |
| Outlaws (Disc 2) | PC | 1.0 | Original | | | |
| Outlaws (Disc 2) | PC | 1.1 | Rerelease | | | |
| Outlaws: Die Gesetzlosen (Disc 1) | PC | 1.1.1 | Original | | | |
| Outlaws: Die Gesetzlosen (Disc 2) | PC | 1.1.1 | Original | | | |
| Outpost 2: Geteilte Bestimmung | PC | 1.0 | Original | | S0011248 | |
| Outwars (Disc 1) | PC | 1.0 | Original | | 0398 Artikelnr. X00-14039 DE | |
| Outwars (Disc 2) | PC | 1.0 | Original | | 0398 Artikelnr. X00-14040 DE | |
| OverBlood | PSX | | Original | | SLES-00770 | |
| OverBlood 2 (Disc 1) | PSX | Rev 1 | Original | | SLES-02187 … | |
| OverBlood 2 (Disc 2) | PSX | Rev 1 | Original | | SLES-12187 … | |
| Oxyd Magnum! Gold Edition | PC | | Game-Pack 3 | | 80227 | |
| O Xephteris Taxideuei stin Ellada Ο Ξεφτέρης ταξιδεύει στην Ελλάδα | PC | | Original | | | |
| Odysseia ΟΔΥΣΣΕΙΑ | PC | 1.8 | Original | | | |
| Oddworld: Abe's Exoddus (Disc 1) | PC | 1.0 | Covermount | | | |
| Oddworld: Abe's Exoddus (Disc 2) | PC | 1.0 | Covermount | | | |
| O.D.T. | PSX | | Original | | SLES-01411 | |
| O.R.B: Off-World Resource Base | PC | | Covermount | | | |
| Obsidian: Alla Frontiera della Logica (Disc 1) | PC | 1.0.001 | Original | | | |
| Obsidian: Alla Frontiera della Logica (Disc 2) | PC | 1.0.001 | Original | | | |
| Obsidian: Alla Frontiera della Logica (Disc 3) | PC | 1.0.001 | Original | | | |
| Obsidian: Alla Frontiera della Logica (Disc 4) | PC | 1.0.001 | Original | | | |
| Obsidian: Alla Frontiera della Logica (Disc 5) | PC | 1.0.001 | Original | | | |
| Oddworld: Abe's Exoddus (Installazione) | PC | 1.0 | Replay | | ABEXPCREI/A1 | |
| Oddworld: Abe's Exoddus (Gioco) | PC | 1.0 | Replay | | ABEXPCREI/A2 | |
| Oddworld: Abe's Exoddus (Disc 1) | PSX | | Original, Platinum | | SLES-01504 … | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original, Platinum | | SLES-11504 … | |
| Oddworld: Abe's Oddysee | PSX | | Original | | SLES-00840 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Covermount | | IB2G-ODDI5 | |
| Odissea: Sulle tracce di Ulisse (Disc 1) | PC | | Original | | ODY-ITA-P01 | |
| Odissea: Sulle tracce di Ulisse (Disc 2) | PC | | Original | | ODY-ITA-P02 | |
| Offensive Offensive War: The Ultimate Strategical Combat Game | PC | | Covermount | | | |
| Oil Tycoon 2 Oil Tycoon 2: Il Ritorno di una Leggenda | PC | | EXA Games | | EXAG020 | |
| Olympic Soccer | PC | | CD-ROM Classic Collection 2 | | | |
| Omnia Junior 1: Enciclopedia: Dizionario | PC | | Covermount | | SIAE 08A01PA | |
| Omnia Junior 2: Storia: Attività interattive | PC | | Covermount | | SIAE 0901PA | |
| Omnia Junior 3: Il Mondo degli Animali | PC | | Covermount | | SIAE1001PA | |
| Oni | PC | 1.0 | Covermount | | | |
| Oni | PC | 1.0 | Covermount | | | |
| Oni | PS2 | 1.02 | Original | | SLES-50178 | |
| Only Fun: Entra anche tu nel mondo dei Videogames | PC | | | | | |
| Open Kart | PC | | I Videogiochi del "Giornalino" | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0.0.4 | Game of the Year Edition (Covermount) | | | |
| Original War (Disc 1) | PC | 1.02 | Covermount | | | |
| Original War (Disc 1) | PC | 1.02 | Original | | CD-W95-V006-IT1 | |
| Original War (Disc 2) | PC | 1.02 | Covermount | | | |
| Original War (Disc 2) | PC | 1.02 | Original | | CD-W95-V006-IT2 | |
| Oro e Gloria: La Strada per El Dorado | PC | | Covermount | | | |
| Oro e Gloria: La Strada per El Dorado | PSX | | Original | | SLES-03186 | |
| Oscar | PC | | Jackson Libri | | | |
| Ostrich Runner | PC | | Microforum | | | |
| Outcast (Disc 1) | PC | | Covermount | | | |
| Outcast (Disc 2) | PC | | Covermount | | | |
| Outlaws (Disco 1) | PC | 1.0 | LucasArts Classic | | 41175.101.IT | |
| Outlaws (Disco 2) | PC | 1.0 | LucasArts Classic | | 41175.102.IT | |
| Outlaws (Disco 1) | PC | 2.0 | Collezione CD-Rom by C.T.O. | | LUC628 | |
| Outlaws (Disco 2) | PC | 2.0 | Collezione CD-Rom by C.T.O. | | LUC628 | |
| Outpost 2: Destini Sospesi | PC | 1.0 | Covermount | | | |
| Over Load | PC | | | | | |
| OverBlood 2 (Disc 1) | PSX | | Original | | SLES-01880 | |
| OverBlood 2 (Disc 2) | PSX | | Original | | SLES-11880 | |
| Osef Minei Mischakim אוסף מיני משחקים | PC | | Original | | | |
| O-to-i-re: Dreamcast Sequencer お・と・い・れ ドリームキャストシーケンサー | DC | 1.002 | Original | | T-32801M | |
| Oasis Road オアシスロード | PSX | | Original | | SLPS 01899 | |
| OASYS/Win V2.0 | FMT | | Original | | B28C7020 | |
| Obaachan no Chiebukuro おばあちゃんの知恵袋 | FMT | | Original | | HMC-169 | |
| Obbligato (Taikenban CD-ROM) オブリガート 体験版CD-ROM | PC | | Demo | | | |
| Obsidian (Disc 1) | MAC | | Original, Great Series | | INR-001, MKM-001 | |
| Obsidian (Disc 1) オブシディアン | PC | | Original | | INR-1003 | |
| Obsidian (Disc 1) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 2) | MAC | | Original, Great Series | | INR-001, MKM-001 | |
| Obsidian (Disc 2) オブシディアン | PC | | Original | | INR-1002 | |
| Obsidian (Disc 2) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 3) | MAC | | Original, Great Series | | INR-001, MKM-001 | |
| Obsidian (Disc 3) オブシディアン | PC | | Original | | INR-1002 | |
| Obsidian (Disc 3) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 4) | MAC | | Original, Great Series | | INR-001, MKM-001 | |
| Obsidian (Disc 4) オブシディアン | PC | | Original | | INR-1002 | |
| Obsidian (Disc 4) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 5) | MAC | | Original, Great Series | | INR-001, MKM-001 | |
| Obsidian (Disc 5) オブシディアン | PC | | Original | | INR-1002 | |
| Obsidian (Disc 5) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Oceans Below オーシャンズ・ビロウ | MAC | | Original | | MSC001 | |
| Oceans Below オーシャンズ・ビロウ | 3DO | | Original | | FZ-SJ2752 | |
| Ocha no Ma Battle お茶の間バトル | PSX | | Bundled with Controller | | SLPM 86681 | |
| Ochazukenori: Kaiki!! Mushi Danshaku no Yakata 御茶漬海苔 怪奇!!蟲男爵の館 | PC | | Original | | | |
| Ochigee Designer Tsukutte Pon! 落ちゲー・デザイナー 作ってポン! | SS | 1.090 | Original | | T-9108G | |
| Oda Nobunaga Den 織田信長伝 | PSX | | Original, Koei the Best | | SLPM 86337 … | |
| Oda Nobunaga Den 織田信長伝 | PC | 1.0 | Original | | KN11-93101 | |
| ODN Palm Power Pack | PALM | | Original | | | |
| Odo Odo Oddity おどおど おっでぃ | PSX | | Hibaihin | | SLPM 80075 | |
| Odo Odo Oddity おどおどおっでぃ | PSX | | Original | | SLPS 00754 | |
| Off-World Interceptor オフ‐ワールド・インターセプター | 3DO | | Original | | FZ-SJ3151 | |
| Off-World Interceptor Extreme オフワールド・インターセプター エクストリーム | PSX | | Original | | SLPS 00122 | |
| Off-World Interceptor Extreme オフワールド・インターセプター エクストリーム | SS | 1.000 | Ketteiban | | T-15901G | |
| Official Fan Book: Circadia: Special CD-ROM オフィシャルファンブック サーカディア | PSX | | Original | | SCZS 94106 | |
| Official Yarudora Fan Book: Double Cast: CD-ROM Special Data-shuu オフィシャルやるドラファンブック ダブルキャスト | PSX | | Original | | SCZS 94101 | |
| Official Yarudora Fan Book: Kisetsu o Dakishimete オフィシャルやるドラファンブック 季節を抱きしめて | PSX | | Original | | SCZS 94102 | |
| Official Yarudora Fan Book: Sampaguita オフィシャルやるドラファンブック サンパギータ | PSX | | Original | | SCZS 94103 | |
| Official Yarudora Fan Book: Yukiwari no Hana: CD-ROM Special Data-shuu オフィシャルやるドラファンブック 雪割りの花 | PSX | | Original | | SCZS 94104 | |
| Ogura Hyakunin Isshu 小倉百人一首 | 3DO | | Original | | SV-0201 | |
| Oh No! オーノー! | PSX | | Original | | SLPS 02764 | |
| Oh-chan no Oekaki Logic おーちゃんのお絵かきロジック | PSX | | Original, SunColle Best, Value 1500 | | SLPS 00093 … | |
| Oh-chan no Oekaki Logic おーちゃんのお絵かきロジック | SS | 1.005 | Original | | T-1508G | |
| Oh-chan no Oekaki Logic 2 おーちゃんのお絵かきロジック2 | PSX | | Original | | SLPS 00345 | |
| Oh-chan no Oekaki Logic 2 おーちゃんのお絵かきロジック2 | PSX | Rev 1 | SunColle Best, Value 1500 | | SLPS 02145 … | |
| Oh-chan no Oekaki Logic 3 おーちゃんのお絵かきロジック3 | PSX | | Value 1500 | | SLPS 03134 | |
| Oh-chan no Oekaki Logic for Palm おーちゃんのお絵かきロジック for Palm | PALM | 1.04 | Original | | | |
| Oh! Bakyuuun オーバキューン | PSX | | Original | | SLPS 02680 | |
| Oh!PC 1998-nen 8-gatsu-gou Tokubetsu Furoku CD-ROM Oh!PC 1998年 8月号 特別付録CD-ROM | PC | | | | OHPC-9808 | |
| Oh!PC 1998-nen 9-gatsu-gou Tokubetsu Furoku CD-ROM Oh!PC 1998年 9月号 特別付録CDーROM | PC | | | | OHPC-9809 | |
| Oh!X 1998 Spring Special CD-ROM (Part 1) | X68K | | | | | |
| Oh!X 1998 Spring Special CD-ROM (Part 2) (Sampler Disc) | X68K | | | | | |
| Oh!X 1999 Spring Special CD-ROM (Part 1) | X68K | | | | | |
| Oh!X 1999 Spring Special CD-ROM (Part 2) (Sampler Disc) | X68K | | | | | |
| Oh!X 1999 Summer Special CD-ROM | X68K | | | | | |
| Oh!X 2000 Spring Special CD-ROM (Part 1) | X68K | | | | | |
| Oh!X 2000 Spring Special CD-ROM (Part 2) | X68K | | | | | |
| Oh!X 2001 Spring Special CD-ROM | X68K | | | | | |
| Oha Suta Dance Dance Revolution おはスタ ダンス ダンス レボリューション | PSX | | Original | | SLPM 86603 | |
| Oha Suta Series 01: Zonapara おはスタシリーズ01 象南波羅~ゾナパラ~ | KSITE | | Original | | 536956 | |
| Oha Suta Series 02: Oha Ska! おはスタシリーズ02 おは スカ | KSITE | | Original | | 538714 | |
| Öhlins Hyper-Rally ハイパーラリー | PSX | | Original | | SLPS 00462 | |
| Oilman オイルマン | 3DO | | Hibaihin | | OIL-9610 | |
| Oja Majo DoReMi Dokkan! Nijiiro ParaDice おジャ魔女どれみドッカ~ン! にじいろパラダイス | PSX | | Original | | SLPS 03497 | |
| Ojousama Express お嬢様特急 | PSX | | Taikenban | | SLPM 80255 | |
| Ojousama Express (Disc 1) お嬢様特急 | PSX | | Original | | SLPS 01495 | |
| Ojousama Express (Disc 1) お嬢様特急 | SS | 1.005 | Original | | T-27803G | |
| Ojousama Express (Disc 2) お嬢様特急 | PSX | | Original | | SLPS 01496 | |
| Ojousama Express (Disc 2) お嬢様特急 | SS | 1.005 | Original | | T-27803G | |
| Ojousama o Nerae!! お嬢様を狙え!! | SS | 1.002 | Original | | T-38101G | |
| Ojousama o Nerae!! お嬢様を狙え!! | SS | 1.003 | Original | | T-38101G | |
| Ojousama Sousamou お嬢様捜査網 | PC-FX | | Original | | FXNHE616 | |
| Okappari-ou 陸釣王 | PSX | | Original | | SLPS 01524 | |
| Okashina Mother Goose: Mixed-Up Mother Goose おかしなマザー・グース | FMT | | Original | | HMB-235 | |
| Okigaru Igo Taikyoku お気軽囲碁対局 | PALM | | Original | | | |
| Okigaru Igo Taikyoku お気軽囲碁対局 | PPC | | Original | | | |
| Okiraku TownsGEAR お気楽 TownsGEAR | FMT | | Bundled with Book | | SBHW-00002 | |
| Okudera Yasuhiko no Sekai o Mezase! Soccer Kids: Nyuumon-hen 奥寺康彦の世界をめざせ! サッカー・キッズ 入門編 | SS | 1.310 | Original | | T-26001G | |
| Ollie King オーリーキング | CHIHIRO | 1.003 | Original | | GDX-0007 | |
| Olympia, Takasago: Virtua Pachi-Slot III オリンピア・高砂 バーチャ・パチスロⅢ | PSX | | Original | | SLPS 01386 | |
| Olympia, Yamasa: Virtua Pachi-Slot II: Jissen! Bishoujo Kouryakuhou オリンピア・山佐 バーチャパチスロⅡ ~実戦!美少女攻略法~ | PSX | | Original | | SLPS 00714 | |
| Olympic Soccer オリンピックサッカー | PSX | | Original | | SLPS 00523 | |
| Olympic Soccer オリンピックサッカー | SS | 1.002 | Original | | T-7304G | |
| Omakase! Savers おまかせ!退魔業 | SS | 1.002 | Original | | GS-9030 | |
| Omega Boost オメガ・ブースト | PSX | | Original, Preview | | SCPS 10020 | |
| Omega Boost オメガ・ブースト | PSX | | Taikenban | | PAPX 90080 | |
| Omiai Commando: Ba-Couple ni Tsukkomi o お見合いコマンドー ~バカップルにつっこみを~ | PSX | | Original | | SLPM 86439 | |
| Omise de Tenshu おみせde店主 | PSX | | Original | | SLPS 01876 | |
| Omizu no Hanamichi お水の花道 | PSX | | Original | | SLPS 02815 | |
| Omoide ni Kawaru Kimi: Memories Off 想い出にかわる君 ~Memories Off~ | DC | 1.001 | Original | | T-19718M | |
| On Air | PC | | Original | | BROWNIE 990201 | |
| One ワン | PSX | | Original | | SLPS 01812 | |
| One Piece Mansion ワンピースマンション | PSX | | Taikenban | | SLPM 80617 | |
| One Piece Mansion ワンピースマンション | PSX | | Original | | SLPM 86837 | |
| One Two Animal: Let's Animal Series 1 ワンツーあにまる レッツあにまるシリーズ1 | PC | | Original | | LAOA-96101 | |
| One Two Smash: Tanoshii Tennis ワン・ツー スマッシュ たのしいテニス | PSX | | Honkakuha de 1300 | | SLPS 02585 | |
| One-derful Theater ONEだふるシアター | X68K | | | | | |
| Onee-san to Issho! Janken Paradise お姉さんといっしょ! じゃんけん パラダイス | 3DO | | Original | | FZ-SJ5251 | |
| Onee-san to Issho! Kisekae Paradise お姉さんといっしょ! 着せ替え パラダイス | 3DO | | Original | | FZ-SJ5252 | |
| Onegai Countdown おねがいカウントダウン | PC | | Original | | YMH-0013 | |
| Ongaku Tkool 3 音楽ツクール3 | PSX | | Original | | SLPS 03161 | |
| Ongaku Tkool: Kanadeeru 2 音楽ツクール かなで~る2 | PSX | | Original | | SLPS 00903 | |
| Oni | PC | 1.00.000 | Original | | MTW-0390 | |
| Oni no Kamen 鬼ノ仮面 | PC | 1.00 | Original | | | |
| The Oni Taiji!!: Mezase! Nidaime Momotarou The鬼退治!! 目指せ!二代目桃太郎 | PSX | | Original | | SLPS 00089 | |
| The Oni Taiji!!: Mezase! Nidaime Momotarou The鬼退治!! 目指せ!二代目桃太郎 | PSX | | Major Wave | | SLPM 86989 | |
| Onigunsou Kuramochi Yuzo no Yatchimasu: Spartan Manshu 鬼軍曹倉持勇造の殺っちます ~スパルタン満州~ | PC | | Original | | | |
| Onii-chan Jushin-chuu お兄ちゃん受信中 | PC | | Original | | | |
| Onikiri-den 鬼斬伝 | PC | | Original | | ZEUS-00001 | |
| Online Games: Dai Guru Guru Onsen オンラインゲームズ 大ぐるぐる温泉 | PS2 | 1.01 | Original | | SLPM 62195 | |
| Only One 2: Bijin Casino Dealer Hitomi: Sei no Roulette オンリーワン2 美人カジノディーラー瞳 性のルーレット | PC | | Original | | ON2-HITO | |
| Only One 2: Naomi: Ai no Inori ga Todoku Toki オンリーワン2 なおみ 愛の祈りが届く時 | PC | 1.0.0.1 | Original | | ON2-NAO | |
| Only You: Seikimatsu no Juliet-tachi Only You ~世紀末のジュリエットたち~ | FMT | | Shokai Gentei | | | |
| Onmyou Taisenki: Byakko Enbu 陰陽大戦記 白虎演舞 | PS2 | 1.01 | EyeToy Camera Doukonban | | SLPS 20416 | |
| Onmyou Taisenki: Byakko Enbu 陰陽大戦記 白虎演舞 | PS2 | 1.01 | Original | | SLPS 20417 | |
| Onsen de Takkyuu 温泉de卓球 | PC | | Original | | | |
| Onsen Ryokou Kakumei: Ich liebe dich.! 温泉旅行革命 ~Ich liebe dich.!~ | PC | 1.00 | Original | | RUCCA-003 | |
| Ooedo Fuusui Ingaritsu: Hanabi 2 大江戸風水因果律 花火2 | PSX | | Original | | SLPS 02814 | |
| Ooedo Renaissance 大江戸ルネッサンス | SS | 1.001 | Original | | T-9104G | |
| Oogami Ichirou Funtou-ki: Sakura Taisen Kayou Show "Beni Tokage" yori (Disc 1) 大神一郎奮闘記 ~サクラ大戦歌謡ショウ「紅蜥蜴」より~ | DC | 1.000 | Original | | HDR-0057 | |
| Oogami Ichirou Funtou-ki: Sakura Taisen Kayou Show "Beni Tokage" yori (Disc 2) 大神一郎奮闘記 ~サクラ大戦歌謡ショウ「紅蜥蜴」より~ | DC | 1.000 | Original | | HDR-0057 | |
| Ookami-teki Monshou: Crest of Wolf 狼的紋章 クレスト・オブ・ウルフ | PCE | | Original | | HCD3044 | |
| Ooumi Nobunaga Den: Geten II 大海信長伝・下天II | PSX | | Original | | SLPS 00874 | |
| Oozora ni Kodawarou! Minna no Kuukou 2 大空にこだわろう! みんなの空港2 | PC | | | | | |
| The Open Golf: History of Turnberry ジ・オープンゴルフ History of Turnberry | PSX | | Original | | SLPS 00418 | |
| Opera House Preview Disc オペラハウス プレビューディスク | PC | | Original | | | |
| Operation Wolf オペレーション・ウルフ | FMT | 1.00 | Ving Vol. 3 | | HMB-126 | |
| The Operative: No One Lives Forever (Disc 1) ノーワンリブスフォーエバー | PC | 1.004, 1.004J | Original | | | |
| The Operative: No One Lives Forever (Disc 2) ノーワンリブスフォーエバー | PC | 1.004, 1.004J | Original | | | |
| Option: Tuning Car Battle オプション チューニングカーバトル | PSX | | Original | | SLPS 01207 | |
| Option: Tuning Car Battle Option チューニングカーバトル | PSX | | Highlight-ban | | SLPM 80203 | |
| Option: Tuning Car Battle Option チューニングカーバトル | PSX | | Taikenban | | SLPM 80206 | |
| Option: Tuning Car Battle オプション チューニングカーバトル | PSX | Rev 1 | PlayStation the Best | | SLPS 91037 | |
| Option: Tuning Car Battle 2 オプション チューニングカーバトル2 | PSX | | Original | | SLPS 01857 | |
| Option: Tuning Car Battle Spec R オプション チューニングカーバトル スペックR | PSX | | Original | | SLPS 02587 | |
| Oracle no Houseki: Jewels of the Oracle オラクルの宝石 Jewels of the Oracle | PSX | | Original | | SLPS 00240 | |
| Oracle no Houseki: Jewels of the Oracle オラクルの宝石 | SS | 1.004 | Original | | T-1511G | |
| Orange Pocket: Cornet オレンジポケット -コルネット- | DC | 1.004 | Original, Shokai Genteiban | | T-18707M, T-18708M | |
| Ore no Ryouri 俺の料理 | PSX | | Original, PlayStation the Best | | SCPS 10099 … | |
| Ore no Ryouri 俺の料理 | PSX | | Taikenban | | PAPX 90089 | |
| Ore no Shikabane o Koete Yuke 俺の屍を越えてゆけ | PSX | | Original, PlayStation the Best, PSone Books, PSone Books (Silver Disc) | | SCPS 10074 … | |
| Ore no Shikabane o Koete Yuke 俺の屍を越えてゆけ | PSX | | Tentou-you Movie Disc | | PCPX 96160 | |
| Ore no Shita de Agake 俺の下であがけ | PC | System3.9 Ver.5.43 | Original | | ALB-005 | |
| Ore no Yotto: Ganbare! Nippon Challenge 俺のヨット ~がんばれ! ニッポン・チャレンジ~ | PSX | | Original | | SLPS 02132 | |
| Ore! Tomba オレっ!トンバ | PSX | | Taikenban | | SLPM 80165 | |
| Ore! Tomba オレっ!トンバ | PSX | | Original | | SLPS 01144 | |
| Oretachi Geesen Zoku: Akumajou Dracula オレたちゲーセン族 悪魔城ドラキュラ | PS2 | 1.01 | Original | | SLPM 62729 | |
| Oretachi Geesen Zoku: Burger Time オレたちゲーセン族 バーガータイム | PS2 | 1.00 | Original | | SLPM 62695 | |
| Oretachi Geesen Zoku: Contra オレたちゲーセン族 魂斗羅 | PS2 | 1.00 | Original | | SLPM 62730 | |
| Oretachi Geesen Zoku: Crazy Climber オレたちゲーセン族 クレイジー・クライマー | PS2 | 1.01 | Original | | SLPM 62627 | |
| Oretachi Geesen Zoku: Karate-dou オレたちゲーセン族 空手道 | PS2 | 1.01 | Original | | SLPM 62628 | |
| Oretachi Geesen Zoku: Moon Cresta オレたちゲーセン族 ムーンクレスタ | PS2 | 1.01 | Original | | SLPM 62645 | |
| Oretachi Geesen Zoku: Nekketsu Kouha Kunio-kun オレたちゲーセン族 熱血硬派くにおくん | PS2 | 1.01 | Original | | SLPM 62706 | |
| Oretachi Geesen Zoku: Nekketsu Koukou Dodgeball-bu オレたちゲーセン族 熱血高校ドッジボール部 | PS2 | 1.00 | Original | | SLPM 62705 | |
| Oretachi Geesen Zoku: Pooyan オレたちゲーセン族 プーヤン | PS2 | 1.01 | Original | | SLPM 62731 | |
| Oretachi Geesen Zoku: Quarth オレたちゲーセン族 クォース | PS2 | 1.02 | Original | | SLPM 62704 | |
| Oretachi Geesen Zoku: Rabio Lepus オレたちゲーセン族 ラビオ レプス | PS2 | 1.00 | Original | | SLPM 62707 | |
| Oretachi Geesen Zoku: Scramble オレたちゲーセン族 スクランブル | PS2 | 1.01 | Original | | SLPM 62626 | |
| Oretachi Geesen Zoku: Sonic Wings オレたちゲーセン族 ~ソニックウィングス~ | PS2 | 1.01 | Original | | SLPM 62646 | |
| Oretachi Geesen Zoku: Super Volleyball オレたちゲーセン族 スーパーバレーボール | PS2 | 1.04 | Original | | SLPM 62660 | |
| Oretachi Geesen Zoku: Terra Cresta オレたちゲーセン族 テラクレスタ | PS2 | 1.04 | Original | | SLPM 62661 | |
| Oretachi Geesen Zoku: Thunder Cross オレたちゲーセン族 サンダークロス | PS2 | 1.02 | Original | | SLPM 62744 | |
| Oretachi Geesen Zoku: Time Pilot オレたちゲーセン族 タイムパイロット | PS2 | 1.01 | Original | | SLPM 62644 | |
| Oretachi Geesen Zoku: Trio the Punch オレたちゲーセン族 トリオ・ザ・パンチ | PS2 | 1.02 | Original | | SLPM 62745 | |
| Oretachi Geesen Zoku: Yie Ar Kung Fu オレたちゲーセン族 イー・アル・カンフー | PS2 | 1.01 | Original | | SLPM 62696 | |
| Orgaslave (Side-1) オルガスレイブ | PC | | Original | | H PT 003-1 | |
| Orgaslave (Side-2) オルガスレイブ | PC | | Original | | H PT 003-2 | |
| Orgazumi (Disc 1) オーガズミー | PC | | Original | | FCG013 | |
| Orgazumi (Disc 2) オーガズミー | PC | | Original | | FCG014 | |
| Original War (Disc 1) (Install Disc) オリジナル ウォー | PC | 1.02 | Original | | | |
| Original War (Disc 2) (GameDisc) オリジナル ウォー | PC | 1.02 | Original | | | |
| Osaka City 大阪 | PHOTO-CD | | Original | | | |
| Osaka Ennichi 大阪緣日 | PC | | Original | | OE-V1.00 | |
| Osaka Naniwa Matenrou 大阪ナニワ摩天楼 | PSX | | Original | | SLPS 02013 | |
| Osananajimi wa Pet Yakuza! 幼なじみはペットヤクザ!体験版 | PC | | Taikenban | | | |
| Oshare Cooking おしゃれクッキング | FMT | Rev A | Original | | HMA-267A | |
| Oshare Cooking II おしゃれクッキングⅡ | FMT | Rev B | Original | | HMA-267B | |
| Oshidashi Zintrick ~ ZinTricK 押し出しジントリック | NGCD | | Original | | ADCD-104 | |
| Oshiete Noobow おしえて ぬ~ぼ~ | FMT | | Original | | HMF-110 | |
| Oshigoto-shiki Jinsei Game: Mezase Shokugyou King お仕事式人生ゲーム めざせ職業王 | PSX | | Original, The Best Takaramono | | SLPM 87316 … | |
| Otenki Kororin お天気ころりん | PSX | | Original | | SLPM 87047 | |
| Othelanian Wars オセラニアン・ウォーズ | PC | | Original | | | |
| Othello World II: Yume to Michi e no Chousen オセロワールドII 夢と未知への挑戦 | PSX | | Original, Fukkokuban | | SLPS 00136 … | |
| Other Life Azure Dreams アザーライフ アザードリームス | PSX | | Original | | SLPM 86047 | |
| Oto to E no Deru Eigo Jisho No. 1: Start with Words 音と絵の出る英語辞書 No.1 「Start with Words」 | FMT | | Original, Rerelease | | HMA-217 | |
| Oto to E no Deru Eigo Jisho No. 2: English in Dream 音と絵の出る英語辞書 No.2 「English in Dream」 | FMT | | Original | | HMB-129 | |
| Oto to E no Deru Eigo Jisho No. 3: Nandemo Illust Eigo Jiten 音と絵の出る英語辞書 No.3 「なんでもいらすとえいごじてん」 | FMT | | Original | | HMB-131 | |
| Oto to E no Deru Eigo Jisho No. 4: Nandemo Illust Eigo Jiten Part 2 音と絵の出る英語辞書 No.4 「なんでもいらすとえいごじてん Part 2」 | FMT | | Original | | HMB-170 | |
| Otogi Story: Tenshi no Shippo おとぎストーリー ~天使のしっぽ~ | PSX | | Original | | SLPS 03531 | |
| Otome Koigokoro Prister 乙女恋心プリスター体験版 | PC | | Taikenban | | | |
| Otomedius (System Disc) オトメディウス | KEA | JAA | Original | | GGGJAA01 | |
| Otomedius (Application Disc 1) オトメディウス | KEA | JAA | Original | | GGGJAA02 | |
| Otomedius (Application Disc 2) オトメディウス | KEA | JAA | Original | | GGGJAA03 | |
| Otona no Asobi おとなの遊び | PSX | | Nichibutsu Collection 2000 | | SLPS 02459 | |