Region | Title | System | Version | Edition | Languages | Serial | Status |
| Out Live: Be Eliminate Yesterday アウトライブ Be Eliminate Yesterday | PSX | | Original | | SLPS 00746 | |
| Out of This World | PC | | Valueware | | CD-ICD-142-0 | |
| Out of This World | 3DO | | Original | | | |
| Out of This World | PC | | Rerelease | | CD-MMC-023-0 | |
| Outbreaker | PC | | Original | | | |
| Outburst | PC | | Classic Value Series | | Product# 99043 | |
| Outcast (Disc 1) | PC | | Original | | OUTCAPC52G/A1 | |
| Outcast (Disc 2) | PC | | Original | | OUTCAPC52G/A2 | |
| Outcast (Disc 1) | PC | | Original | | OUTCAPC52F/A1 | |
| 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 | |
| Outcast (Disc 1) | PC | | Covermount | | | |
| Outcast (Disc 2) | PC | | Covermount | | | |
| Outcast (Disc 1) | PC | | Original | | 42831-9110TC | |
| Outcast (Disc 2) | PC | | Original | | 42831-9110TC | |
| Outdoor Wander Land アウトドアワンダーランド | MAC | | Original | | ILL-940715 | |
| Outer World アウター・ワールド | 3DO | | Original | | FZ-SJ3451 | |
| Outlast: A Reading for Information Game | PC | | Original | | HH824 | |
| Outlaw Golf | PC | | Original | | RM-OUTGOLF-UK | |
| Outlaw Racers | PC | | Sold Out Software | | | |
| Outlaws (Disc 1) | PC | | Original | | | |
| Outlaws (Disc 1) | PC | | M6 Multimedia | | M6IMM6 | |
| Outlaws (Disc 2) | PC | | Original | | | |
| Outlaws (Disc 2) | PC | | M6 Multimedia | | M6IMM6 | |
| Outpost | PC | | Original | | S390021012ZZ2 | |
| Outpost | PC | | SierraOriginals | | S4941220Z12Z2 | |
| Outpost | PC | | Original | | S 390121012ZZZ | |
| Outpost | PC | | Original | | S725430 | |
| Outpost 2: Divided Destiny | PC | | SierraOriginals | | | |
| Outrage | PC | | Original | | | |
| OutRun 2006: Coast 2 Coast (Disc 1) | PC | | Original | | | |
| OutRun 2006: Coast 2 Coast (Disc 2) | PC | | Original | | | |
| Over 1000 Games: The Complete Encyclopedia of Games (Disc 1) | PC | | Original | | | |
| Over 1000 Games: The Complete Encyclopedia of Games (Disc 2) | PC | | Original | | | |
| 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 | | | |
| Over 350 Jigsaw Puzzles | PC | | Original | | 012163 | |
| Over 350 Solitaire Games | PC | | Original | | | |
| Over Drivin' DX オーバードライビンDX | PSX | | Original | | SLPS 00327 | |
| Over Drivin' DX: Rally Edition オーバードライビンDX ラリーエディション | PSX | | Hibaihin | | SLPM 80032 | |
| Over Drivin' II オーバードライビンⅡ | PSX | | Original | | SLPS 00895 | |
| Over Drivin' III: Hot Pursuit オーバードライビンⅢ | PSX | | Original | | SLPS 01593 | |
| Over Drivin' III: Hot Pursuit オーバードライビンⅢ | PSX | | Taikenban Disc | | SLPM 80298 | |
| Over Drivin' IV オーバードライビンⅣ | PSX | | Taikenban Disc | | SLPM 80437 | |
| Over Drivin' IV オーバードライビンⅣ | PSX | | Original | | SLPS 02099 | |
| Over Load | PC | | | | | |
| OverBlood | PSX | | Original | | SLES-00768 | |
| OverBlood | PSX | | Original | | SLES-00769 | |
| OverBlood | PSX | | Original | | SLES-00770 | |
| OverBlood オーバーブラッド | PSX | | Original, PlayStation the Best | | SLPS 00392 … | |
| OverBlood オーバーブラッド | PSX | | Major Wave | | SLPM 86641 | |
| OverBlood | PSX | | Original | | SLUS-00464 | |
| OverBlood 2 (Disc 1) | PSX | | Original | | SLES-01879 | |
| OverBlood 2 (Disc 2) | PSX | | Original | | SLES-11879 | |
| OverBlood 2 (Disc 1) | PSX | | Original | | SLES-01880 | |
| OverBlood 2 (Disc 2) | PSX | | Original | | SLES-11880 | |
| OverBlood 2 オーバーブラッド2 | PSX | | Special Movie-ban | | PAPX 90046 … | |
| OverBlood 2 (Disc 1) オーバーブラッド2 | PSX | | Original | | SLPS 01261 | |
| OverBlood 2 (Disc 2) オーバーブラッド2 | PSX | | Original | | SLPS 01262 | |
| OverBlood 2: The "East Edge" File オーバーブラッド2 -The "East Edge" File- | PSX | | Premium Disc | | SLPM 80270 | |
| 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 | |
| OverTop オーバートップ | NGCD | | Original | | ADCD-011 | |
| De Overval: Over Dwangmiddelen en Getuigenverhoor | CDI | | Original | | ovrvl 01 | |
| The Oxfordshire Golf Club | PC | | Original | | EAE05101006D | |
| Oxide Oxyde | PC | | Dynamite | | DE-006 | |
| Oxyd Magnum! Gold Edition | PC | | Game-Pack 3 | | 80227 | |
| Oyaji Hunter Mahjong おやじハンター・マージャン | 3DO | | Original, Sample | | IMP-SF0703 | |
| Oyaji no Jikan: Nee-chan Hanafuda de Shoubu ya! おやじの時間 ~ねーちゃん花札で勝負や!~ | PSX | | Original | | SLPS 02591 | |
| Oyaji no Jikan: Nee-chan Mahjong de Shoubu ya! おやじの時間 ~ねーちゃん麻雀で勝負や!~ | PSX | | Renkaban | | SLPS 03262 | |
| Oyaji no Jikan: Nee-chan Tsuri Iku de! おやじの時間 ね~ちゃん釣り行くで! | PSX | | Original | | SLPS 02590 | |
| Oyako Entertainment Series: TV Kamishibai Vol. 1 親子エンタテインメントシリーズ ~てれび紙芝居Vol.1~ | PSX | | Original | | SLPM 86393 | |
| Oynayarak Ogreniyorum 1 Oynayarak Öğreniyorum 1 | PC | | Original | | | |
| Oyunlarla Dil Bilgisi Oyunlarla Matematik | PC | | Original | | | |
| Oz no Mahoutsukai: Another World: Rung Rung オズの魔法使い ~Another World~ ルングルング | PSX | | Original | | SLPS 02335 | |
| Oz: The Magical Adventure | PC | | Original | | | |
| Ozaki Yutaka: Eyes: "Hakushi no Sanran" Yori 尾崎 豊 eyes「白紙の散乱」より | PHOTO-CD | | | | CAT.908753-7 | |
| Ozawa-Ken+ | PC | | Original | | | |
| Ozzie's World オジィーズワールド | PC | | Original | | ASOW-71110 | |
| Ozzie's World | PC | | Original | | | |
| Official Sega Dreamcast Magazine Vol. 11: February 2001 | DC | 0.500 | | | | |
| Orly Pervoj mirovoj Орлы Первой мировой | PC | 02.19.07 | Original | | | |
| The Oregon Trail 4th Edition (Disc 1) | PC | 1 | Original | | OTF744AE-CD1 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1 | Rerelease | | OTF744CE-CD2 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1 | Original | | OTF744AE-CD2 | |
| The Oregon Trail 4th Edition (Disc 3) | PC | 1 | Original | | OTF744AE-CD3 | |
| O.R.B: Off-World Resource Base | PC | 1.0 | Original | | 22434CD | |
| 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 | | | |
| ObsCure (Disc 1) | PC | 1.0 | Original | | PCO457CD | |
| ObsCure (Disc 2) | PC | 1.0 | Original | | PCO457CD | |
| ObsCure (Disc 3) | PC | 1.0 | Original | | PCO457CD | |
| ObsCure (Disc 4) | PC | 1.0 | Original | | PCO457CD | |
| ObsCure (Disc 5) | PC | 1.0 | Original | | PCO457CD | |
| Obsidian (Disc 1) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 2) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 3) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 4) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian (Disc 5) オブシディアン | PC | 1.0 | Original | | INR-1003 | |
| Obsidian | PC | 1.0 | Demo | | | |
| Oda Nobunaga Den 織田信長伝 | PC | 1.0 | Original | | KN11-93101 | |
| Oddballz: Your Wacky Computer Petz | PC | 1.0 | Original | | CS090370 | |
| Oddworld: Abe's Exoddus (Disc 1) | PC | 1.0 | Covermount | | | |
| Oddworld: Abe's Exoddus (Disc 2) | PC | 1.0 | Covermount | | | |
| Oddworld: Abe's Exoddus (Installazione) | PC | 1.0 | Replay | | ABEXPCREI/A1 | |
| Oddworld: Abe's Exoddus (Gioco) | PC | 1.0 | Replay | | ABEXPCREI/A2 | |
| Odyssey: The Legend of Nemesis | MAC | 1.0 | Original | | | |
| Oil Platform Simulator | PC | 1.0 | Original | | | |
| Oil Tycoon | PC | 1.0 | Original | | | |
| Oktoberfest Wiesn-Gaudi | PC | 1.0 | Original | | | |
| Omar Sharif Bridge | PC | 1.0 | Original | | | |
| Omikron: The Nomad Soul (Disc 1) | PC | 1.0 | Original | | | |
| Omikron: The Nomad Soul (Disc 2) | PC | 1.0 | Original | | | |
| Omikron: The Nomad Soul (Disc 3) | PC | 1.0 | Original | | | |
| Ominous Horizons Ominous Horizons: A Paladin's Calling | PC | 1.0 | Original | | | |
| On the Ball: League Edition | PC | 1.0 | Original | | | |
| Oni | PC | 1.0 | Original | | | |
| Oni | PC | 1.0 | Covermount | | | |
| Oni | PC | 1.0 | Covermount | | | |
| Oni Они | PC | 1.0 | | | | |
| Oni | PC | 1.0 | PC Best Buy | | 177588 | |
| Oni | PC | 1.0 | Original | | | |
| Open Season Boog & Elliot | PC | 1.0 | Demo | | | |
| Open Season (Disc 1) | PC | 1.0 | Original | | 683131-CD1 | |
| Open Season (Disc 2) | PC | 1.0 | Original | | 683131-CD2 | |
| Open Season (Disc 3) | PC | 1.0 | Original | | 683131-CD3 | |
| Opening Night | PC | 1.0 | Original | | #HCD646A | |
| Opening Night: Behind The Scenes | PC | 1.0 | Original | | #HCD646B | |
| 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 | 1.0 | Original | | MOPFCDUS00 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | FXX08903223D1 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.0 | Original | | FXX08903223D2 | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.0 | Original | | FXX08903223D2 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0 | Original | | | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.0 | Original | | | |
| OptImage Media Showcase | CDI | 1.0 | Original | | | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.0 | Original | | OTA744AE-CD1 | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.0 | Original | | 380859-CD | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.0 | Scholastic | | 380859-CD WP2 | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.0 | Original | | 380859A-CD | |
| Oregon Trail II | PC | 1.0 | Original | | | |
| The Oregon Trail | PC | 1.0 | Original | | | |
| Outer Ridge | PC | 1.0 | Original | | SPI004 | |
| Outlaws (Disc 1) | PC | 1.0 | Original | | 9511830 | |
| Outlaws (Disc 2) | PC | 1.0 | Original | | 9511831 | |
| Outlaws (Disc 1) | PC | 1.0 | Original | | | |
| Outlaws (Disc 2) | PC | 1.0 | Original | | | |
| Outlaws (Disco 1) | PC | 1.0 | LucasArts Classic | | 41175.101.IT | |
| Outlaws (Disco 2) | PC | 1.0 | LucasArts Classic | | 41175.102.IT | |
| Outpost 2: Destini Sospesi | PC | 1.0 | Covermount | | | |
| Outpost 2: Divided Destiny | PC | 1.0 | Original | | S0011246 | |
| Outpost 2: Geteilte Bestimmung | PC | 1.0 | Original | | S0011248 | |
| Outwars (Disc 1) | PC | 1.0 | Original | | 0298 Part No. X03-63527 | |
| Outwars (Disc 2) | PC | 1.0 | Original | | 0298 Part No. X03-57509 | |
| Outwars (Disc 1) | PC | 1.0 | Original | | 0398 Artikelnr. X00-14039 DE | |
| Outwars (Disc 2) | PC | 1.0 | Original | | 0398 Artikelnr. X00-14040 DE | |
| Outwars (Disc 1) | PC | 1.0 | Original | | 0298 Part No. X03-63527 | |
| Outwars (Disc 2) | PC | 1.0 | Original | | 0298 Part No. X03-57509 | |
| Ovech'i bega Овечьи бега | PC | 1.0 | Original | | | |
| Outlaws (Disc 1) | PC | 1.0 Build 3 | Original | | 9511830 | |
| Outlaws (Disc 1) | PC | 1.0 Build 3 | Bundle Version Diamond OEM | | 644430 | |
| Outlaws (Disc 2) | PC | 1.0 Build 3 | Original | | 9511831 | |
| Outlaws (Disc 2) | PC | 1.0 Build 3 | Bundle Version Diamond OEM | | 644431 | |
| Odens Öga Odens Öga! | PC | 1.0.0 | Original | | | |
| The Outforce | PC | 1.0.0.0 | Original | | | |
| 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 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.0.0.4 | Game of the Year Edition (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 | | | |
| Off-Road: Wide Open Test Drive Off-Road: Wide Open | PS2 | 1.00 | Original | | SLES-50232 | |
| Official PlayStation 2 Magazine Demo 1 | PS2 | 1.00 | | | SCED-50065 | |
| Official PlayStation 2 Magazine Demo 2 | PS2 | 1.00 | | | SCED-50066 | |
| Official PlayStation 2 Magazine Demo 3 | PS2 | 1.00 | | | SCED-50067 | |
| Official PlayStation 2 Magazine Demo 5 | PS2 | 1.00 | | | SCED-50140 | |
| Offroad Extreme! Special Edition | PS2 | 1.00 | Original | | SLES-54109 | |
| On the Ball: World Cup Edition | PC | 1.00 | Original | | | |
| Oni no Kamen 鬼ノ仮面 | PC | 1.00 | Original | | | |
| Online Start-Up Disc 4.0 | PS2 | 1.00 | | | SCUS-97357 | |
| Online Start-Up Disc v1.0 Disco de Inicio en Línea v1.0 | PS2 | 1.00 | Original | | PBPX 95250 … | |
| Online Start-Up Disc v3.5: Broadband Only | PS2 | 1.00 | Original | | PBPX 95247 | |
| Online Start-Up Disc v3.5: Broadband Only | PS2 | 1.00 | Original | | PBPX-95246 | |
| Onsen Ryokou Kakumei: Ich liebe dich.! 温泉旅行革命 ~Ich liebe dich.!~ | PC | 1.00 | Original | | RUCCA-003 | |
| Open Season (Disc 1) | PC | 1.00 | Original | | 5004904-CD 1 | |
| Open Season (Disc 2) | PC | 1.00 | Original | | 5004904-CD 2 | |
| Open Season (Disc 3) | PC | 1.00 | Original | | 5004904-CD 3 | |
| Open Season (Disc 1) | PC | 1.00 | Original | | | |
| Operation Wolf オペレーション・ウルフ | FMT | 1.00 | Ving Vol. 3 | | HMB-126 | |
| 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: 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: Rabio Lepus オレたちゲーセン族 ラビオ レプス | PS2 | 1.00 | Original | | SLPM 62707 | |
| Otostaz オトスタツ | PS2 | 1.00 | Original | | SCPS 11024 | |
| Otostaz オトスタツ | PS2 | 1.00 | Taikenban | | PAPX 90228 | |
| Otostaz オトスタツ | PS2 | 1.00 | Taikenban | | PAPX 90226 | |
| Otostaz オトスタツ | PS2 | 1.00 | Taikenban | | SCPS 11020 | |
| Oni | PC | 1.00.000 | Original | | MTW-0390 | |
| Off-World Interceptor Extreme | SS | 1.000 | Original | | T-15908H-50 | |
| 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 | |
| Off-World Interceptor Extreme | SS | 1.000 | Original | | T-15908H | |
| Official Sega Dreamcast Magazine Vol. 9: December 2000 | DC | 1.000 | | | IGN9 | |
| 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 | |
| Orion's Puzzle Collection | DC | 1.000 | Unlicensed | | | |
| Ostrov Nanda Остров Нанда | PC | 1.000 | Original | | | |
| Omikron: The Nomad Soul | DC | 1.001 | Original | | T-36807N | |
| Omoide ni Kawaru Kimi: Memories Off 想い出にかわる君 ~Memories Off~ | DC | 1.001 | Original | | T-19718M | |
| Ooedo Renaissance 大江戸ルネッサンス | SS | 1.001 | Original | | T-9104G | |
| Ooga Booga | DC | 1.001 | Original | | 51140 | |
| Ousama Game (Disc 1) (Ichigo Disc) 王様げーむ | SS | 1.001 | Original | | T-21904G | |
| Ousama Game (Disc 2) (Momo Disc) 王様げーむ | SS | 1.001 | Original | | T-21904G | |
| Outtrigger | DC | 1.001 | Original | | MK-51102-50 | |
| 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 | |
| Ojousama o Nerae!! お嬢様を狙え!! | SS | 1.002 | Original | | T-38101G | |
| 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 | |
| Ojousama o Nerae!! お嬢様を狙え!! | SS | 1.003 | Original | | T-38101G | |
| Ollie King オーリーキング | CHIHIRO | 1.003 | Original | | GDX-0007 | |
| Ouka Houshin: Ouka Sakishi Toki 央華封神 ~央華咲きし刻~ | DC | 1.003 | Original | | T-38704M | |
| Outtrigger | DC | 1.003 | Original | | 51102 | |
| 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 | 1.004 | Game of the Year Edition (Xplosiv) | | EI-1685-2 | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition (BestSeller Series) | | JCPL11, S0026695 | |
| 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 | 1.004 | Game of the Year Edition | | S0025037 | |
| The Operative: No One Lives Forever (Disc 1) (Game Disc) | MAC | 1.004 | MacPlay | | | |
| The Operative: No One Lives Forever (Disc 1) | PC | 1.004 | Game of the Year Edition | | | |
| The Operative: No One Lives Forever (Disc 2) | PC | 1.004 | Game of the Year Edition, Game of the Year Edition (BestSeller Series), Game of the Year Edition (Covermount) | | JCPL11, S0026179, S0026696 | |
| 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 | |
| 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 | | | |
| 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 | |
| Ojousama Express (Disc 1) お嬢様特急 | SS | 1.005 | Original | | T-27803G | |
| Ojousama Express (Disc 2) お嬢様特急 | SS | 1.005 | Original | | T-27803G | |
| Outtrigger アウトトリガー | DC | 1.008 | Original | | HDR-0118 | |
| Obliterate | PS2 | 1.01 | Original | | SLES-53355 … | |
| Ocean Commander | PS2 | 1.01 | Original | | SLES-55047 | |
| Off Road | PS2 | 1.01 | Original | | SLES-55032 | |
| Offroad Extreme! | PS2 | 1.01 | Original | | SLES-52751 | |
| Oil Tycoon | PC | 1.01 | Original | | | |
| Okage: Shadow King | PS2 | 1.01 | Original | | SCUS 97129 | |
| 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 | |
| Online Start-Up Disc v3.0 | PS2 | 1.01 | | | PBPX-95242 | |
| Online Start-Up Disc v3.0 | PS2 | 1.01 | | | SCUS 97425 | |
| 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 | |
| Operation Air Assault | PS2 | 1.01 | Original | | SLES-52572 | |
| Operation Air Assault 2 | PS2 | 1.01 | Original | | SLES-54804 | |
| 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: 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: Pooyan オレたちゲーセン族 プーヤン | PS2 | 1.01 | Original | | SLPM 62731 | |
| 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: 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: 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 | |
| The Orion Conspiracy | PC | 1.01 | Original | | | |
| Ougon Kishi Garo 黄金騎士 牙狼 | PS2 | 1.01 | Genteiban | | SLPS 20462 | |
| Ougon Kishi Garo 黄金騎士 牙狼 | PS2 | 1.01 | Original | | SLPS 20463 | |
| Outlive | PC | 1.01 | Original | | | |
| Outlive | PC | 1.01 | Original | | | |
| The Operational Art of War II | PC | 1.01.02 | Xplosiv | | EI-1259-3 | |
| Official Sega Dreamcast Magazine Vol. 3: January 2000 | DC | 1.010 | | | IGN2 | |
| Official Sega Dreamcast Magazine Vol. 5: May 2000 | DC | 1.010 | | | | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.01E | Enhanced Education Version | | 480599-CD | |
| Oni | PS2 | 1.02 | Original, Platinum | | SLES-50134 … | |
| Oni | PS2 | 1.02 | Original | | SLES-50176 | |
| Oni | PS2 | 1.02 | Original | | SLES-50177 | |
| Oni | PS2 | 1.02 | Original | | SLES-50178 | |
| Oni | PS2 | 1.02 | Original | | SLES-50179 | |
| Online Start-Up Disc 4.0: Broadband Only | PS2 | 1.02 | Bundled with PS2 | | PBPX 95248 … | |
| Online Start-Up Disc v3.0 | PS2 | 1.02 | Original | | PBPX-95239 | |
| 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: 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: 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 | |
| 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 | |
| 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 | | | |
| Official Sega Dreamcast Magazine Vol. 2: November 1999 | DC | 1.020 | | | IGN1 | |
| Official Sega Dreamcast Magazine Vol. 4: March 2000 | DC | 1.020 | | | IGN3 | |
| Official Sega Dreamcast Magazine Vol. 7: September 2000 | DC | 1.020 | | | IGN7 | |
| Official Sega Dreamcast Magazine Vol. 8: November 2000 | DC | 1.020 | | | IGN8 | |
| O.R.B.: Orbital'nye Resursnye Bazy О.Р.Б.: Орбитальные Ресурсные Базы | PC | 1.03 | 1C: Kollekciya igrushek | | | |
| Otona no Gal-jong: Kimi ni Haneman! おとなのギャル雀 ~きみにハネ満!~ | PS2 | 1.03 | Jaleco the Best | | SLPM 62549 | |
| 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 | | | |
| 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 | |
| Les Ours Berenstain: Comme des Grands | CDI | 1.05 | | | 812 0063 | |
| Official Sega Dreamcast Magazine Vol. 6: July 2000 | DC | 1.050 | | | IGN6 | |
| Ontdek het Onbekende Nederland | CDI | 1.06 | Original | | 814 0104 | |
| Ochigee Designer Tsukutte Pon! 落ちゲー・デザイナー 作ってポン! | SS | 1.090 | Original | | T-9108G | |
| One Must Fall 2097 One Must Fall 2097 CD-ROM | PC | 1.1 | ROMWARE | | ROM 10017 | |
| One Must Fall 2097 | PC | 1.1 | Demo | | | |
| The Oregon Trail 4th Edition (Disc 1) | PC | 1.1 | Rerelease | | OTF744BE-CD1 | |
| The Oregon Trail 4th Edition (Disc 2) | PC | 1.1 | Rerelease | | OTF744BE-CD2 | |
| The Oregon Trail 4th Edition (Disc 3) | PC | 1.1 | Rerelease | | OTF744BE-CD3 | |
| The Oregon Trail 5th Edition: Adventures Along the Oregon Trail | PC | 1.1 | Rerelease, Southwestern School Set | | 380859B-CD | |
| The Oregon Trail | PC | 1.1 | Original | | #HCD606 | |
| Outlaws (Disc 1) | PC | 1.1 | Rerelease | | | |
| Outlaws (Disc 2) | PC | 1.1 | Rerelease | | | |
| Outpost | PC | 1.1 | Rerelease | | S725431 | |
| Odnazhdy' v Chikago Однажды в Чикаго | PC | 1.1.0.0 | Original | | | |
| Outlaws: Die Gesetzlosen (Disc 1) | PC | 1.1.1 | Original | | | |
| Outlaws: Die Gesetzlosen (Disc 2) | PC | 1.1.1 | Original | | | |
| Operation WinBack | PS2 | 1.10 | Original | | SLES-50155 | |
| On-Robot Он-Робот | PC | 1.14SB | 1C: Igrushki | | | |
| Operation Neptun | PC | 1.2 | Original | | ONT844AW-CD | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.2 | Original | | OTA744CE-CD1 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.2 | Rerelease | | OTA744BE-CD1 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 2) | PC | 1.2 | Original | | OTA744BE-CD2 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 3) | PC | 1.2 | Original | | OTA744BE-CD3 | |
| The Oregon Trail | PC | 1.2 | Original | | #HCD706 | |
| The Oregon Trail | PC | 1.2 | Original | | #HCD706 | |
| Outpost 2: Divided Destiny | PC | 1.2.0.5 | Original | | | |
| Outpost 2: Divided Destiny | PC | 1.2.0.5 | Original | | | |
| The Omega Stone: Riddle of the Sphinx II (Disc 1) | PC | 1.2.3.2 | Original | | | |
| The Omega Stone: Riddle of the Sphinx II (Disc 2) | PC | 1.2.3.2 | Original | | | |
| The Omega Stone: Riddle of the Sphinx II (Disc 3) | PC | 1.2.3.2 | Original | | | |
| The Omega Stone: Riddle of the Sphinx II (Disc 4) | PC | 1.2.3.2 | Original | | | |
| Oregon Trail II + Logic Quest | PC | 1.2/1.0 | Original | | | |
| Oni | PS2 | 1.20 | Original | | SLUS-20064 | |
| Official Sega Dreamcast Magazine Vol. 10: January 2001 | DC | 1.200 | | | IGN10 | |
| Oudou Aniki 王道兄貴 | PC | 1.20b | Original | | | |
| One Unit Whole Blood | PC | 1.21 | Original | | 04-16459CD1 | |
| The Oregon Trail | PC | 1.21 | | | | |
| Operation Neptune | PC | 1.22 | Original | | ONT744CE-CD | |
| The Oregon Trail | PC | 1.22 | Smart Saver | | ORT844AE-CD | |
| Operation Neptune | PC | 1.23 | The ClueFinders: Math Ages 9-12 | | ONT744EE-CD | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.2a | Bundle Version Compaq Presario OEM | | | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 1) | PC | 1.3 | The Learning Company | | OAE744BE-CD1 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 2) | PC | 1.3 | The Learning Company | | OAE744BE-CD2 | |
| The Oregon Trail 3rd Edition: Pioneer Adventures (Disc 3) | PC | 1.3 | The Learning Company | | OAE744BE-CD3 | |
| Oregon Trail II | PC | 1.3 | Smart Saver | | 0TT744AE-CD | |
| Oregon Trail II | PC | 1.3 | Smart Saver | | 381032-CD/i401ha | |
| Oregon Trail II: 25th Anniversary Limited Edition | PC | 1.3 | Original, SoftKey | | #OTR744AE-CD | |
| Operation Flashpoint: Gold Upgrade | PC | 1.30 | Original | | MOFUCDUS00 | |
| Operation Flashpoint: Gold Upgrade | PC | 1.30 | Original, Gold Edition | | MOFUCDEU00, MOFUCDUS00 | |
| Oregon Trail II | PC | 1.31 | Rerelease | | HCD744BE-CD | |
| Oregon Trail II | PC | 1.31 | Rerelease | | #HCD744AE-CD | |
| 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 | |
| Oregon Trail II | PC | 1.32 | Rerelease | | #HCD744CE-CD | |
| Operation Flashpoint: Cold War Crisis | PC | 1.46 | Sold Out Software | | | |
| Operation Flashpoint: Cold War Crisis | PC | 1.46 | Sold Out Software | | | |
| Operation Flashpoint: Holodnaja vojna Операция Flashpoint: Холодная война | PC | 1.46 | Original | | | |
| Ovation | ARCH | 1.48S | | | 00139 | |
| Outpost | PC | 1.5 | Rerelease, Sierra Originals | | | |
| Outpost | PC | 1.51 | Schweinepreise | | S390122CZ12ZZ | |
| Oni 奥妮 | PC | 1.7 | Original | | | |
| Operation Flashpoint: Resistance | PC | 1.75 | Original | | MOFRCDEU00 | |
| Operation Flashpoint: Resistance | PC | 1.75 | Original | | MOFRCDUS00 | |
| Odysseia ΟΔΥΣΣΕΙΑ | PC | 1.8 | Original | | | |
| Operation Flashpoint: Soprotivlenie Operation Flashpoint: Сопротивление | PC | 1.85 | | | | |
| Oxford Handbook of Clinical Medicine for PDAs: Seventh Edition | PALM | 10.0.05/2007.9.7 | | | | |
| 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 (CD Installieren) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (CD Abspielen) | PC | 2.0 | Original | | | |
| Oddworld: Abe's Exoddus (Installatie Disk) | PC | 2.0 | Budget | | MMICDR 5280 | |
| Oddworld: Abe's Exoddus (Install) | PC | 2.0 | Original | | 04-15993CD1 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Original | | IB2G-ODD5 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Original | | IB2G-ODDG5 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Covermount | | IB2G-ODDI5 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Channelware | | 04-15303 | |
| Oddworld: Abe's Oddysee | PC | 2.0 | Original | | 04-12608CD | |
| Outlaws (Disc 1) | PC | 2.0 | LucasArts Classics | | 3000009.101.UK | |
| Outlaws (Disc 2) | PC | 2.0 | LucasArts Classics | | 3000009.102.UK | |
| Outlaws (Disc 1) | PC | 2.0 | Collection LucasArts | | | |
| Outlaws (Disc 2) | PC | 2.0 | Collection LucasArts | | | |
| 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 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 1) | PC | 2.0 | Rerelease | | 9511830 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
| Outlaws (Disc 2) | PC | 2.0 | Rerelease | | 9511831 | |
| 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 | |
| Olympic Soccer | SS | 2.000 | Original | | T-7904H-09, T-7904H-50 | |
| Olympic Soccer | SS | 2.000 | Original | | T-07904H-18 | |
| Olympic Soccer | SS | 2.000 | Original | | T-7904H | |
| OutRun 2 | CHIHIRO | 2.000 | Original | | GDX-0004A | |
| One Must Fall 2097 | PC | 2.1 | The Smile Edition | | CDR3016 | |
| Oscar Wilde's The Selfish Giant | PC | 2.10 | Original | | MQ 13-004-144 | |
| One Must Fall: Battlegrounds | PC | 2090 | Original | | | |
| One Must Fall: Battlegrounds | PC | 2090 | Original | | | |
| The Oregon Trail | PC | 3.0.1 | Slash | | CDRM1239790 | |
| The Oregon Trail: Classic Edition | PC | 3.0.1 | SoftKey | | POT144CE-CD | |
| ODS Robot Challenge | PC | 5.0.1r26 | Teacher's Edition | | | |
| Obitel' T'my Обитель Тьмы | PC | 5.02 04/07/03 | Original | | | |
| ODS Air Explorer | PC | 5.0r134 | Teacher's Edition | | | |
| ODS Air Explorer | PC | 5.0r134 | Teacher's Edition | | | |
| ODS Amazing Art Corner | PC | 5.0r134 | Teacher's Edition | | | |
| ODS Carnival Math | PC | 5.0r134 | Teacher's Edition | | | |
| ODS Carnival Math | PC | 5.0r134 | Teacher's Edition | | | |
| Oz: The Magical Adventure | PC | 7.0.0.198 | Rerelease | | 92785 | |
| Operaciya Silent Storm (Disc 1) Операция Silent Storm | PC | Aug 11 2003 | 1C: Igroteka | | | |
| Operaciya Silent Storm (Disc 2) Операция Silent Storm | PC | Aug 11 2003 | 1C: Igroteka | | | |
| Outlaws (Demonstration Program) | PC | Demo 1.0 CD Build 3 | Demo | | 644230 | |
| Official U.S. PlayStation Magazine Demo Disc 43 | PSX | EDC | | | SCUS-94634 | |
| 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 | |
| OnHand Chess / Sega Swirl Lite | PALM | PDA103-01 | Original | | PDA103-01 | |
| OnHand Sports Games / Sega Swirl Lite | PALM | PDA105-01 | OnHand Double Pack (Sports Games/Astrologer) | | PDA105-01 | |
| OnHand Complete Astrologer OnHand Complete Astrologer: Horoscopes & More! | PALM | PDA108-01 | OnHand Double Pack (Sports Games/Astrologer) | | PDA108-01 | |
| Out of This World | 3DO | RE | 3DO Maniac Pack | | | |
| Oddworld: Abe's Oddysee | PSX | Rev 1 | Original, Greatest Hits | | SLUS-00190 | |
| 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 … | |
| Onside Complete Soccer | PSX | Rev 1 | Original | | SLES-00079 | |
| 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 | |
| OverBlood 2 (Disc 1) | PSX | Rev 1 | Original | | SLES-01879 … | |
| OverBlood 2 (Disc 2) | PSX | Rev 1 | Original | | SLES-11879 … | |
| OverBlood 2 (Disc 1) | PSX | Rev 1 | Original | | SLES-02187 … | |
| OverBlood 2 (Disc 2) | PSX | Rev 1 | Original | | SLES-12187 … | |
| Oddworld: Abe's Oddysee | PSX | Rev 2 | Greatest Hits | | SLUS-00190 | |
| 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 | |
| Ore no Shita de Agake 俺の下であがけ | PC | System3.9 Ver.5.43 | Original | | ALB-005 | |
| Outcry (Disc 1) Outcry: The Dawn | PC | Version DPV 1.0 | Original | | PCO596CD | |
| Outcry (Disc 2) Outcry: The Dawn | PC | Version DPV 1.0 | Original | | PCO596CD | |