Poids Mi-Moyens Hommes
 | Junie Browning | 1-1-0 UFC | #4121 |  |
 | Junior Hernandez | 2-0-1 REC | #1750 |  |
 | Justin Burlinson | 3-1-0 REC | #2343 |  |
 | Justin Edwards | 2-5-0 UFC | #3201 | |
 | Jutaro Nakao | 1-1-0 UFC | #4676 |  |
 | K.J. Noons | 2-3-0, 1NC UFC | #3240 | |
 | Kacper Koziorzebski | 5-2-0 REC | #1078 |  |
 | Kaik Brito | 5-3-0 REC | #594 |  |
 | Kamal Dzhalavov | 1-0-0 REC | #2634 |  |
 | Kamaru Usman | 16-3-0 UFC | #25 |  |
 | Karim Adem | #7730 |  | |
 | Karim Ghajji | 0-3-0 REC | #4072 |  |
 | Karim Rabei | 0-1-0, 1NC REC | #5235 |  |
 | Karl Amoussou | 0-2-0 REC | #3665 | |
 | Karo Parisyan | 8-4-0, 1NC UFC | #1206 | |
 | Karol Skrzypek | 0-1-0 REC | #5475 | |
 | Kassius Kayne | 0-1-0 REC | #7334 | |
 | Kazushi Sakuraba | 1-0-0, 1NC UFC | #3689 | |
 | Keita Nakamura | 4-7-0 UFC | #2219 | |
 | Keith Wisniewski | 0-4-0 UFC | #3972 | |