Region | Title | System | Version | Edition | Languages | Serial | Status |
| O.D.T. | PSX | | Demo | | SLUS-90043 | |
| 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 (Disc 1) | PSX | | Original | | SLUS-00710 … | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original | | SLUS-00731 … | |
| Oddworld: Abe's Exoddus + Duke Nukem: Time To Kill + B-Movie | PSX | | Demo | | SLED-01608 | |
| Oddworld: Abe's Oddysee | PSX | Rev 1 | Original, Greatest Hits | | SLUS-00190 | |
| Oddworld: Abe's Oddysee | PSX | Rev 2 | Greatest Hits | | SLUS-00190 | |
| Official PlayStation Magazine Best Games Ever 2000 | PSX | | | | SCED-03375 | |
| Official U.S. PlayStation Magazine Demo Disc 01 | PSX | | | | SCUS-94189 | |
| Official U.S. PlayStation Magazine Demo Disc 02 | PSX | | | | SCUS-94198 | |
| Official U.S. PlayStation Magazine Demo Disc 10 | PSX | | | | SCUS-94217 | |
| Official U.S. PlayStation Magazine Demo Disc 11 | PSX | | | | SCUS-94218 | |
| Official U.S. PlayStation Magazine Demo Disc 28 | PSX | | | | SCUS-94436 | |
| Official U.S. PlayStation Magazine Demo Disc 29 | PSX | | | | SCUS-94437 | |
| Official U.S. PlayStation Magazine Demo Disc 31 | PSX | | | | SCUS-94499 | |
| Official U.S. PlayStation Magazine Demo Disc 42 | PSX | | | | SCUS-94631 | |
| Official U.S. PlayStation Magazine Demo Disc 43 | PSX | EDC | | | SCUS-94634 | |
| Official U.S. PlayStation Magazine Demo Disc 52 | PSX | | | | SCUS-94662 | |
| Official U.S. PlayStation Magazine Demo Disc 54 | PSX | | | | SCUS-94664 | |
| Ogre Battle: Limited Edition | PSX | | Original | | SLUS-00467 | |
| Omega Boost | PSX | | Original | | SCUS-94449 | |
| One | PSX | | Demo | | SLED-01170 | |
| One Piece Mansion | PSX | | Original | | SLES-03723 | |
| OPSM Best PS One Games Ever Official Australian PlayStation Magazine Demo 44 | PSX | | | | SCED-03239 | |
| OverBlood 2 (Disc 1) | PSX | Rev 1 | Original | | SLES-01879 … | |
| OverBlood 2 (Disc 2) | PSX | Rev 1 | Original | | SLES-11879 … | |
| Oddworld: Abe's Exoddus + Duke Nukem: Time to Kill + Duke Nukem: 3D | PSX | | | | SLED-01655 | |
| Omega Boost | PSX | | Original | | SCES-02120 | |
| Omega Boost オメガ・ブースト | PSX | | Original, Preview | | SCPS 10020 | |
| Oddworld: L'Exode d'Abe (Disc 1) | PSX | | Original | | SLES-01502 | |
| Oddworld: L'Exode d'Abe (Disc 2) | PSX | | Original | | SLES-11502 | |
| Oddworld: Abe's Exoddus (Disc 1) | PSX | | Original | | SLES-01503 | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original | | SLES-11503 | |
| OverBlood 2 (Disc 1) | PSX | Rev 1 | Original | | SLES-02187 … | |
| Oddworld: Abe's Exoddus (Disc 1) | PSX | | Original, Platinum | | SLES-01504 … | |
| Oddworld: Abe's Exoddus (Disc 2) | PSX | | Original, Platinum | | SLES-11504 … | |
| Oro e Gloria: La Strada per El Dorado | PSX | | Original | | SLES-03186 | |
| OverBlood 2 (Disc 1) | PSX | | Original | | SLES-01880 | |
| OverBlood 2 (Disc 2) | PSX | | Original | | SLES-11880 | |
| Oda Nobunaga Den 織田信長伝 | PSX | | Original, Koei the Best | | SLPM 86337 … | |
| 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: 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 | |
| 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 … | |
| Ojousama Express (Disc 1) お嬢様特急 | PSX | | Original | | SLPS 01495 | |
| Ojousama Express (Disc 2) お嬢様特急 | PSX | | Original | | SLPS 01496 | |
| 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 | |
| Omega Boost オメガ・ブースト | PSX | | Taikenban | | PAPX 90080 | |
| 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 | |
| Ooedo Fuusui Ingaritsu: Hanabi 2 大江戸風水因果律 花火2 | PSX | | Original | | SLPS 02814 | |
| Ore no Ryouri 俺の料理 | PSX | | Original, PlayStation the Best | | SCPS 10099 … | |
| Ore! Tomba オレっ!トンバ | PSX | | Taikenban | | SLPM 80165 | |
| Ore! Tomba オレっ!トンバ | PSX | | Original | | SLPS 01144 | |
| 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 … | |
| Otogi Story: Tenshi no Shippo おとぎストーリー ~天使のしっぽ~ | PSX | | Original | | SLPS 03531 | |
| Oumagatoki 逢魔が時 | PSX | | Original, PSone Books | | SLPS 03235 … | |
| Oumagatoki 逢魔が時 プレミアム"FAN"ディスク | PSX | | Premium Fan Disc | | SLPM 80623 | |
| 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 | |