Sorted alphabetically by last name · 2769 fighters
| Name | Nickname | |
|---|---|---|
| KT | Kazuki Tokudome | |
| KV | Kazula Vargas | |
| KS | Kazushi Sakuraba | "The Gracie Hunter" |
| KK | Keigo Kunihara | |
| KN | Keiichiro Nakamura | |
| KY | Keiichiro Yamamiya | |
| KN | Keita Nakamura | "K-Taro" |
| KB |
| Keith Berish |
| "Sha Bang Bang" |
| KH | Keith Hackney | "The Giant Killer" |
| KJ | Keith Jardine | "The Dean of Mean" |