| Game Name | System |
|---|
| Oliver and Company (1989)(Coktel Vision)(M5)[cr Empire] | Atari ST |
| Olivetti L1 M20 | MAME |
| Olivetti L1 M40 | MAME |
| Olivia's Mystery (Japan) | SNES |
| Olli & Lissa - The Ghost Of Shilmoore Castle (1986)(Firebird) | ZX Spectrum Z80 |
| Olli & Lissa - The Ghost Of Shilmoore Castle (1986)(Firebird)[a2] | ZX Spectrum Z80 |
| Olli & Lissa - The Ghost Of Shilmoore Castle (1986)(Firebird)[a] | ZX Spectrum Z80 |
| Olli & Lissa - The Ghost of Shilmoore Castle (E) | C64 Tapes |
| Olli & Lissa - The Ghost of Shilmoore Castle + Mad Nurse (E) | C64 PP |
| Olli & Lissa II - Halloween (1987)(Firebird) | ZX Spectrum (TAP) |
| Olli & Lissa II - Halloween (1987)(Firebird) | ZX Spectrum Z80 |
| Olli & Lissa III - The Candlelight Adventure (1989)(Codemasters) | ZX Spectrum (TAP) |
| Olli & Lissa III - The Candlelight Adventure (1989)(Codemasters) | ZX Spectrum Z80 |
| Olli & Lissa III - The Candlelight Adventure (1989)(Codemasters)[a] | ZX Spectrum Z80 |
| Olli and Lissa - Ghost of Shilmoore (UK) (1987) | CPC |
| Olli and Lissa - Ghost of Shilmoore (UK) (1987) [a1] | CPC |
| Olli and Lissa - Ghost of Shilmoore (UK) (1987) [a2] | CPC |
| Olli and Lissa 3 (E) | C64 Tapes |
| Olli and Lissa 3 - The Candlelight Adventure (UK) (1989) | CPC |
| Olli and Lissa 3 - The Candlelight Adventure (UK) (1989) [h1] | CPC |
| Olli and Lissa 3 - The Candlelight Adventure (UK) (1989) [t1] | CPC |
| Ollie King (GDX-0007) | MAME |
| Ollie Octopus' Sketch-Pad (1983)(Storm Software) | ZX Spectrum Z80 |
| Ollie's Follies (1984)(Fanda)[cr Steve & Bruce][k-file] | Atari 800 |
| Ollie's Follies (E) | C64 Tapes |
| Olympia | Atari 800 |
| Olympia (Dutch) (Bellfruit) (Scorpion 1) | MAME |
| Olympia Lexikon | Atari 800 |
| Olympiad | Atari 800 |
| Olympiad (1986)(Atlantis Software) | ZX Spectrum Z80 |
| Olympiad (UK) (1986) | CPC |
| Olympiad (UK) (1986) [a1] | CPC |
| Olympiad (UK) (1986) [a2] | CPC |
| Olympian Games (Russia) | MAME |
| Olympic Challenge (1984)(Century City Software) | ZX Spectrum (TAP) |
| Olympic Decathlon (1981)(Microsoft)[a][nib] | Apple2 |
| Olympic Decathlon (1981)(Microsoft)[nib] | Apple2 |
| Olympic Decathlon (1985)(Alligata)[ODLOAD start] [SSD] | BBC Micro |
| Olympic Decathlon (1985)(Alligata)[a][ODLOAD start] [SSD] | BBC Micro |
| Olympic Decathlon (1985)(Alligata)[h 8-Bit][bootfile-TBI-122] [SSD] | BBC Micro |
| Olympic Decathlon (1985)(Alligata)[h TSTH][bootfile] [SSD] | BBC Micro |
| Olympic Dual (19xx)(Antic)[k-file] | Atari 800 |
| Olympic Games | MAME |
| Olympic Games Multilanguage (1996)(US Gold)(En-De) | DOS |
| Olympic Games Winners Edition (1996)(US Gold) | DOS |
| Olympic Gold (Bellfruit) (set 1, UK) (Scorpion 2/3) | MAME |
| Olympic Gold (Bellfruit) (set 1, UK, Protocol) (Scorpion 2/3) | MAME |
| Olympic Gold (Bellfruit) (set 2, UK, 10GBP Jackpot) (Scorpion 2/3) | MAME |
| Olympic Gold (Bellfruit) (set 2, UK, 10GBP Jackpot, Protocol) (Scorpion 2/3) | MAME |
| Olympic Gold (Europe) | Genesis |
| Olympic Gold (Europe) (En,Fr,De,Es,It,Nl,Pt,Sv) | SMS |
| Olympic Gold (Europe) (En,Fr,De,Es,It,Nl,Pt,Sv) (v1.1) | Game Gear |
| Olympic Gold (German) (Nova) (MPU4) (set 1) | MAME |
| Olympic Gold (German) (Nova) (MPU4) (set 2) | MAME |
| Olympic Gold (Japan) | Genesis |
| Olympic Gold (Japan, USA) (En,Fr,De,Es,It,Nl,Pt,Sv) | Game Gear |
| Olympic Gold (Korea) (En,Fr,De,Es,It,Nl,Pt,Sv) | SMS |
| Olympic Gold (USA) | Genesis |
| Olympic Gold (USA) (Alt) | Genesis |
| Olympic Hockey Nagano '98 (Europe) (En,Fr,De,Es) | N64 |
| Olympic Hockey Nagano '98 (Japan) | N64 |
| Olympic Hockey Nagano '98 (USA) | N64 |
| Olympic Hot Stuff (TAS 5 Reel System) | MAME |
| Olympic I.Q. (Asia) (Unl) (NES) | NES |
| Olympic Skier (1986)(Americana) | Atari 800 |
| Olympic Soccer '92 (set 1) | MAME |
| Olympic Soccer '92 (set 2) | MAME |
| Olympic Soccer '92 (set 3) | MAME |
| Olympic Soccer (1996)(US Gold) | DOS |
| Olympic Soccer (E) | PSX |
| Olympic Soccer (E) | Saturn |
| Olympic Soccer (GER) | Saturn |
| Olympic Soccer (USA) | PSX2PSP |
| Olympic Soccer [NTSC-U] | PSX |
| Olympic Soccer [U] | PSX |
| Olympic Summer Games (Europe) | SNES |
| Olympic Summer Games (USA) | SNES |
| Olympic Summer Games (USA) | PSX2PSP |
| Olympic Summer Games (USA, Europe) | GB |
| Olympic Summer Games (USA, Europe) | Genesis |
| Olympic Summer Games [NTSC-U] | PSX |
| Olympicon (1984)(Microtechnica) | ZX Spectrum Z80 |
| Olympicon (1984)(Microtechnica) | ZX Spectrum (TAP) |
| Olympics (1984)(Matthew Bradshaw) | ZX Spectrum (TAP) |
| Olympics (1984)(Matthew Bradshaw)[Part 1 of 2] | ZX Spectrum Z80 |
| Olympics (1984)(Matthew Bradshaw)[Part 2 of 2] | ZX Spectrum Z80 |
| Olympimania (1984)(Automata UK) | ZX Spectrum Z80 |
| Olympimania (1984)(Automata UK) | ZX Spectrum (TAP) |
| Olympimania (1984)(Automata UK)[a] | ZX Spectrum Z80 |
| Olympique de Marseille | Amiga |
| Olympique de Marseille (1994)(Ocean) | DOS |
| Olympus | MAME |
| Olympus no Tatakai (Japan) | NES |
| Omakase Savers (J) | Saturn |
| Omar | Atari 800 |
| Omar Sharif's Bridge | Amiga |
| Omar Sharif's Bridge (1992)(Oxford Softworks)[b] | Atari ST |
| Omar Sharif's Bridge (1992)(Oxford Softworks)[cr Elite] | Atari ST |
| Omaze | Atari 800 |
| Omega | Amiga |
