| Atari 2600 cart. |  Kaboom! Model PAG-010 | 1981 | Activision, Inc. Santa Clara, CA, USA 47875 |
| Apple II 5.25 disk |  Kabul Spy | 1981 | Sirius Soft., Inc. Sacramento, CA, USA |
| Commodore PET cass. | Kadath P | 1981 | Unknown |
| Handheld game | Kageninja Model 16266 | 1981 | Bandai Co., Ltd. Japan |
| Sharp MZ-80B type-in | Kakezan Game | 1981 | Dempa Shinbunsha Japan |
| RCA COSMAC VIP type-in | Kaleidoscopic Life | 1981 | Association of Computer Experimenters |
| Sharp MZ-80K type-in | Kamo vs Sakuma | 1981 | Dempa Shinbunsha Japan |
| Arcade Video game | Kaos | 1981 | GPi Game Plan, Inc. IL, USA |
| Apple II 5.25 disk | Kaves of Karkhan Model 10KK2 | 1981 | Level-10 |
| Sharp MZ-80K type-in | Keiba Game | 1981 | Dempa Shinbunsha Japan |
| Bally Astrocade type-in | Keno II 2.0 | 1981 | Fabris, Robert San Jose, CA, USA |
| Apple II 5.25 disk | Keyboard Golf | 1981 | Softsmith Soft. |
| Arcade Video game | Kick Man Model 513 | 1981 | Midway Mfg. Co. Schiller Park, IL, USA |
| Arcade Video game | Kick Man Model 515 | 1981 | Midway Mfg. Co. Schiller Park, IL, USA |
| Arcade Video game | Kick Man Model 968 | 1981 | Midway Mfg. Co. Schiller Park, IL, USA |
| Apple II 5.25 disk | Kid Venture #1: Little Red Riding Hood Model 041-0030 | 1981 | Adventure International |
| Apple II 5.25 disk | Kid Venture #1: Little Red Riding Hood Model 042-0030 | 1981 | Adventure International |
| TRS-80 cass. | Kid Venture #2: Twas the Night before Christmas Model 011-0083 | 1981 | Adventure International |
| TRS-80 cass. | Kid Venture #3: Old McDonald's Farm Model 011-0124 | 1981 | Adventure International |
| Apple II type-in | Kidnapped P | 1981 | SoftSide Publications, Inc. |
| Atari 400/800 type-in | Kidnapped P | 1981 | SoftSide Publications, Inc. |
| Applied Technology Microbee cass. | Killer Beetles | 1981 | Dubois & McNamara Soft. |
| Commodore VIC-20 type-in | Killer Comet | 1981 | Commodore Business Machines, Inc. |
| Apple II 5.25 disk | King Cribbage | 1981 | Hayden Book Co. |
| Video Slot Machine | King Derby | 1981 | Tazmi |
| Video Slot Machine | King Derby | 1981 | CEI Casino Electronics, Inc. Las Vegas, NV, USA |
| Pinball | King Kong | 1981 | LTD Sao Paulo, Brazil |
| PTC SOL-20 cass. | Kingdom P | 1981 | Unknown |
| RCA COSMAC VIP type-in | Kingdom - A Tiny Basic Simulation Game | 1981 | Association of Computer Experimenters |
| Sinclair ZX-81 cass. | Kingdom of Nam | 1981 | Microgame Simulations |
| Sharp MZ-80K type-in | Kinko-yaburi Game | 1981 | Kosaido Publishing |
| Strength Tester | Knock Down | 1981 | NAMCO, Ltd. Japan |
| TRS-80 disk | Knossos | 1981 | Med Systems |
| Arcade Video game | KO Punch | 1981 | SEGA Enterprises, Ltd. Tokyo, Japan |
| Arcade Video game |  Korosuke Roller | 1981 | Kural Electric, Ltd. |
| TRS-80 type-in | Krazy Talk | 1981 | SoftSide Publications, Inc. |
| Sinclair ZX-81 cass. | Labyrinth | 1981 | Axis Soft. |
| Acorn Atom cass. | Labyrinth | 1981 | Bug-Byte London, England |
| Arcade Video game | Lady Bug | 1981 | Universal Co., Ltd Tokyo, Japan |
| Coin-op Misc. game | Lap King | 1981 | Polar Bear Enterprises, Inc. Mt. Clemens, MI, USA |
