| First | Last | Nickname | Ht. | Wt. | Reach | Stance | W | L | D | Belt |
|---|---|---|---|---|---|---|---|---|---|---|
| Roberto | Romero | El Charro Negro | 5' 8" | 155 lbs. | 70.0" | Orthodox | 8 | 4 | 1 | |
| Mara | Romero Borella | 5' 6" | 125 lbs. | 69.0" | Orthodox | 12 | 9 | 0 | ||
| Cortavious | Romious | 5' 4" | 135 lbs. | 68.0" | Southpaw | 9 | 3 | 0 | ||
| Juancamilo | Ronderos | 100 | 5' 3" | 125 lbs. | 64.0" | Southpaw | 4 | 2 | 0 | |
| Rongzhu | 5' 9" | 155 lbs. | 72.0" | Orthodox | 25 | 6 | 0 | |||
| Jesse | Ronson | The Body Snatcher | 5' 10" | 155 lbs. | 70.0" | Southpaw | 21 | 12 | 0 | |
| George | Roop | 6' 1" | 135 lbs. | 72.0" | Orthodox | 15 | 13 | 1 | ||
| Joao | Roque | 5' 6" | 155 lbs. | -- | Orthodox | 7 | 2 | 4 | ||
| Aaron | Rosa | 6' 4" | 205 lbs. | 77.0" | Orthodox | 18 | 6 | 0 | ||
| Charles | Rosa | Boston Strong | 5' 9" | 145 lbs. | 69.0" | Switch | 14 | 8 | 0 | |
| Karol | Rosa | 5' 5" | 135 lbs. | 67.0" | Orthodox | 18 | 6 | 0 | ||
| Jacob | Rosales | The Lil Badger | 5' 11" | 155 lbs. | 74.0" | Orthodox | 13 | 7 | 0 | |
| Raul | Rosas Jr. | El Nino Problema | 5' 9" | 135 lbs. | 67.0" | Switch | 10 | 1 | 0 | |
| Hilarie | Rose | 5' 3" | 115 lbs. | 63.0" | Orthodox | 4 | 2 | 0 | ||
| Jake | Rosholt | 6' 1" | 185 lbs. | -- | Orthodox | 12 | 5 | 0 | ||
| Jared | Rosholt | 6' 2" | 265 lbs. | 75.0" | Orthodox | 14 | 4 | 0 | ||
| Kevin | Rosier | 6' 4" | 275 lbs. | -- | Orthodox | 2 | 6 | 0 | ||
| Zach | Rosol | -- | 243 lbs. | -- | 3 | 2 | 0 | |||
| Shannon | Ross | The Turkish Delight | 5' 6" | 125 lbs. | 66.0" | Switch | 13 | 9 | 0 | |
| Nick | Rossborough | Leatherface | 6' 5" | 205 lbs. | -- | 26 | 19 | 1 | ||
| Kristian | Rothaermel | 6' 0" | 205 lbs. | -- | Open Stance | 4 | 3 | 0 | ||
| Ben | Rothwell | 6' 4" | 265 lbs. | 78.0" | Orthodox | 39 | 14 | 0 | ||
| Rick | Roufus | 6' 0" | 207 lbs. | -- | Southpaw | 4 | 6 | 0 | ||
| Khalil | Rountree Jr. | 6' 1" | 205 lbs. | 76.0" | Southpaw | 14 | 6 | 0 |