| Title | Year | Genre |
|---|---|---|
| Obake no Q Tarou - Wan Wan Panic | 1985 | Arcade |
| Obocchamakun | 1991 | Board game |
| Oeka Kids - Anpanman no Hiragana Daisuki | 1991 | Arcade |
| Oeka Kids - Anpanman to Oekaki Shiyou!! | 1990 | Arcade |
| Oishinbo - Kyukyoku no Menu 3bon Syoubu | 1989 | Adventure |
| Okkotoshi Puzzle Tonjan!? | 1989 | Puzzle |
| Olympic IQ | 1991 | Puzzle |
| Olympus no Tatakai - Ai no Densetsu | 1988 | Adventure |
| Onyanko Town | 1985 | Arcade |
| Operation - Secret Storm | 1992 | Action |
| Operation Wolf | 1989 | Gun shooter |
| Orb-3D | 1990 | Puzzle |
| Osomatsu-Kun - Back to the Me no Deppa no Maki | 1989 | Adventure |
| Otaku no Seiza - An Adventure in the Otaku Galaxy | 1991 | RPG |
| Othello | 1988 | Puzzle |
| Outlanders | 1987 | Adventure |
| Over Horizon | 1991 | Shooter |
| Overlord | 1993 | Adventure |
