| | Knockout (PR2057) (Mazooma) (Scorpion 4) (set 2) (clone of: sc4knok) | 1969 | Mazooma | sc4knokc | | 0.00 |
| | Knockout (PR7061) (Mazooma) (Scorpion 4) (set 1) | 1969 | Mazooma | sc4knok | | 0.00 |
| | Knockout (PR7061) (Mazooma) (Scorpion 4) (set 2) (clone of: sc4knok) | 1969 | Mazooma | sc4knoka | | 0.00 |
| | Knockout Punch Club (Global) (EPOCH) (set 1) | 1969 | Global | ep_kopcl | | 0.00 |
| | Knockout Punch Club (Global) (EPOCH) (set 2) (clone of: ep_kopcl) | 1969 | Global | ep_kopcla | | 0.00 |
| | Knockout Punch Club (Global) (EPOCH) (set 3) (clone of: ep_kopcl) | 1969 | Global | ep_kopclb | | 0.00 |
 | Knuckle Bash | 1993 | Toaplan | kbash | Fighter / Versus Co-op | 4.00 |
| | Knuckle Bash 2 (bootleg) | 1999 | bootleg | kbash2 | | 0.00 |
 | Knuckle Heads (Japan) (clone of: knckhead) | 1992 | Namco | knckheadj | | 0.00 |
| Knuckle Heads (World) | 1992 | Namco | knckhead | Fighter / Versus | 7.20 |
 | Knuckle Joe (set 1) | 1985 | Seibu Kaihatsu (Taito license) | kncljoe | Platform / Fighter | 5.89 |
| Knuckle Joe (set 2) (clone of: kncljoe) | 1985 | Seibu Kaihatsu (Taito license) | kncljoea | Platform / Fighter | 0.00 |
 | KO Punch | 1981 | Sega | kopunch | Misc. | 0.00 |
| | Koi Koi Part 2 | 1982 | Kiwako | koikoi | | 0.00 |
| | Koi Koi Shimasho | 1995 | Visco | koikois | | 0.00 |
 | Koi Koi Shimasho 2 - Super Real Hanafuda (Japan) | 1997 | Visco | koikois2 | Tabletop / Hanafuda *Mature* | 0.00 |
 | Koi no Hotrock (Japan) (clone of: rockrage) | 1986 | Konami | rockragej | | 0.00 |
 | Kokontouzai Eto Monogatari (Japan) | 1994 | Visco | eto | Puzzle / Drop | 4.79 |
| | Kokoroji 2 | 1994 | Sega | kokoroj2 | | 0.00 |
| | Kollon (V2.04J) | 2003 | Taito | kollon | | 4.78 |
