| K-D Lab | — | 1995 | information technology |
| K. Amusement Leasing Co. | — | 1972 | video game industry |
| Kabam | San Francisco | 2006 | video game industry |
| Kadokawa Corporation | Kabukiza Tower | 2014 | — |
| Kadokawa Shoten | Chiyoda | November 10, 1945 | video game industry |
| Kairosoft | Nishi-Shinjuku | September 2007 | video game industry |
| Kaizen Game Works | — | 2018 | — |
| Kalisto Entertainment | Bordeaux | 1992 | video game industry |
| Kalypso Media | Worms | 2006 | video game industry |
| Kaos Studios | New York City | 2006 | video game industry |
| Karoshi Corporation | — | 2003 | — |
| Katauri Interactive | Kaliningrad | 2004 | — |
| KCET | — | — | — |
| Keen Software House | Prague | 2010 | video game industry |
| Kerzoven | — | — | video game industry |
| Ketchapp | Paris | 2014 | video game publishing |
| Key | Osaka | July 21, 1998 | video game industry |
| Kid Onion Studio | London | — | — |
| Killerfish Games | Adelaide | — | video game industry |
| Kinetic Games | Southampton | October 21, 2020 | — |
| King | London | September 2002 | — |
| KISS | — | — | — |
| Kite Games | — | — | video game industry |
| Kitfox Games | Montreal | — | video game industry |
| Kixeye | San Francisco | 2007 | video game industry |
| KLab | Roppongi Hills Mori Tower | August 2000 | video game development |
| Klei Entertainment | Vancouver | July 2005 | video game industry |
| Knowledge Adventure | — | — | video game industry |
| Koei Tecmo America | Burlingame | 2010 | — |
| Koei Tecmo Europe | Letchworth Garden City | August 8, 2002 | — |
| Koei Tecmo Games | Yokohama | 2011 | video game industry |
| Koei Tecmo Singapore | Singapore | August 2004 | — |
| Komar Games | Simferopol | June 15, 2010 | — |
| Konami Computer Entertainment Japan | Yebisu Garden Place, Tokyo, Roppongi Hills Mori Tower | April 1996 | video game industry |
| Konami Computer Entertainment Osaka | — | April 1995 | video game industry |
| Konfa Games | Saint Petersburg | — | video game industry |
| Kongregate | San Francisco | 2006 | — |
| Koninklijke Philips NV | Amsterdam, Eindhoven | May 15, 1891 | consumer electronics industry |
| KORION | Ludwigsburg | — | — |
| KR Games | — | 2016 | video game industry |
| Krea Medie | — | — | — |
| Kronos Digital Entertainment | Pasadena | 1993 | video game industry |
| KSS | — | — | video game industry |
| Kunos Simulazioni | Campagnano di Roma | 2005 | video game industry |
| Kuro Games | Guangzhou | 2017 | video game industry |
| Kutoka Interactive | Montreal | — | CD-ROM |