| First | Last | Nickname | Ht. | Wt. | Reach | Stance | W | L | D | Belt |
|---|---|---|---|---|---|---|---|---|---|---|
| JJ | Okanovich | The Bosnian Bomber | 5' 11" | 155 lbs. | 76.0" | Orthodox | 7 | 1 | 0 | |
| Bolaji | Oki | The Zulu Warrior | 5' 10" | 155 lbs. | 73.0" | Orthodox | 9 | 2 | 0 | |
| Kazuki | Okubo | 5' 11" | 175 lbs. | -- | Orthodox | 7 | 9 | 0 | ||
| Masakatsu | Okuda | -- | -- | -- | 8 | 5 | 0 | |||
| Aleksei | Oleinik | The Boa Constrictor | 6' 2" | 240 lbs. | 80.0" | Orthodox | 60 | 17 | 1 | |
| Michal | Oleksiejczuk | Hussar | 6' 0" | 185 lbs. | 74.0" | Southpaw | 19 | 9 | 0 | |
| Rafaello | Oliveira | Tractor | 5' 8" | 155 lbs. | 71.0" | Orthodox | 17 | 8 | 0 | |
| Charles | Oliveira | Do Bronxs | 5' 10" | 155 lbs. | 74.0" | Orthodox | 35 | 10 | 0 | |
| Jorge | Oliveira | 6' 1" | 205 lbs. | -- | 5 | 3 | 1 | |||
| Ednaldo | Oliveira | Lula | 6' 5" | 205 lbs. | -- | Orthodox | 17 | 3 | 1 | |
| Alex | Oliveira | Cowboy | 5' 11" | 170 lbs. | 76.0" | Orthodox | 22 | 12 | 1 | |
| Maria | Oliveira | Spider-Girl | 5' 6" | 115 lbs. | 69.0" | Orthodox | 13 | 7 | 0 | |
| Bruno | Oliveira | 6' 4" | 205 lbs. | 80.0" | Orthodox | 8 | 2 | 0 | ||
| Saimon | Oliveira | 5' 4" | 135 lbs. | 72.0" | Orthodox | 18 | 5 | 0 | ||
| Vinicius | Oliveira | LokDog | 5' 9" | 135 lbs. | 70.0" | Switch | 21 | 3 | 0 | |
| Ravena | Oliveira | Kenoudy | 5' 5" | 115 lbs. | 65.0" | Orthodox | 7 | 2 | 1 | |
| Wendell | Oliveira Marques | The Machine | 5' 10" | 170 lbs. | -- | Orthodox | 29 | 10 | 0 | |
| Felipe | Olivieri | 5' 9" | 155 lbs. | -- | Orthodox | 14 | 5 | 0 | ||
| Andy | Ologun | 6' 0" | 154 lbs. | -- | Orthodox | 3 | 1 | 0 | ||
| Shana | Olsen | Rock Solid | 5' 7" | 145 lbs. | -- | 5 | 2 | 0 | ||
| Casey | Olson | The Underdog | 5' 7" | 145 lbs. | -- | Orthodox | 14 | 5 | 0 | |
| Dennis | Olson | 6' 0" | 170 lbs. | -- | 14 | 11 | 0 | |||
| Cameron | Olson | Cap'n Crunch | 6' 1" | 205 lbs. | 75.0" | Orthodox | 7 | 3 | 0 | |
| Gadzhi | Omargadzhiev | 6' 1" | 170 lbs. | 71.0" | Switch | 13 | 2 | 0 |