Combattants Etats-Unis
| 2101 |  | Roland Payne | 0-1-0 UFC | #4891 |  |
| 2102 |  | Roland Pruden | 1-1-0 REC | #3298 | |
| 2103 |  | Roli Delgado | 1-2-0 UFC | #4699 | |
| 2104 |  | Roman Faraldo | 2-2-0 REC | #4146 | |
| 2105 |  | Roman Puga | 3-0-0 REC | #1431 | |
| 2106 |  | Roman Salazar | 0-2-0, 1NC UFC | #3955 | |
| 2107 |  | Romero Cotton | 1-2-0 REC | #5582 | |
| 2108 |  | Ron Faircloth | #7560 | | |
| 2109 |  | Ron Humphrey | 1-0-0 REC | #2454 | |
| 2110 |  | Ron Stallings | 1-2-0 UFC | #4016 | |
| 2111 |  | Ron Van Clief | 0-1-0 UFC | #4772 | |
| 2112 |  | Ron Waterman | 2-1-1 UFC | #3665 | |
| 2113 |  | Ronald Jhun | 0-1-0 UFC | #7194 | |
| 2114 |  | Ronda Rousey | 6-2-0 UFC | #143 | |
| 2115 |  | Ronnie Gibbs | 1-0-0 REC | #3107 | |
| 2116 |  | Ronnie Lawrence | 2-1-0, 1NC UFC | #3565 | |
| 2117 |  | Ronny Hauser | 0-1-0 REC | #7401 | |
| 2118 |  | Roosevelt Roberts | 4-5-0, 1NC UFC | #1833 | |
| 2119 |  | Rory Light | 1-0-0 REC | #7623 | |
| 2120 |  | Rory Markham | 1-2-0 UFC | #3996 | |
| 2121 |  | Rory Singer | 2-2-0 UFC | #4103 | |
| 2122 |  | Rose Namajunas | 12-7-0 UFC | #63 | |
| 2123 |  | Roxanne Modafferi | 4-8-0 UFC | #2002 | |
| 2124 |  | Roy Nelson | 9-10-0 UFC | #770 | |
| 2125 |  | Royce Alger | 0-2-0 UFC | #5013 | |