| O Tac-Tic |
| OAX |
| Obliterator |
| Obsidian |
| Ocean Conqueror |
| Ocean Dynamite Compilation |
| OCP Art Studio |
| Octoplex |
| Oddjob - The Disc Utility Package |
| Oeil De Set, L' |
| Off Shore Warrior |
| Official Father Christmas |
| Oh Mummy |
| Oilmania |
| Oink! The Game |
| Old Sam's Saloon Gamble Machine |
| Ole |
| Ole Toro |
| Olli and Lissa - Ghost of Shilmoore |
| Olli and Lissa 3 - The Candlelight Adventure |
| Olympiad |
| Omega Dimension |
| Omega Planete Invisible |
| Omeyad |
| Omnicop |
| On Cue |
| On the Oche |
| On The Run |
| One |
| One Man and His Droid |
| Operation a Trous |
| Operation Gunship |
| Operation Hanoi |
| Operation Hormuz |
| Operation Nemo |
| Operation Thunderbolt |
| Operation Wolf |
| Optimux Basic Programs |
| Optimux Disc-Copying Utilities |
| Oriental Games |
| Orifice from Outer Space, The |
| Orion |
| Ormuz |
| Orphee |
| Ortho Repere |
| Orthogus |
| Osprey! |
| Othello |
| Othello |
| Othello Master |
| Othello-Reversi |
| Out of this World |
| Out Run |
| Out Run Europa |
| Outboard |
| Outlaw |
| Overlander |
| Overlord 2 |
| Overscan Utility System |
| Oxphar |
| Oxyda |
