Active players are listed in bold.
| O' | Patrick O'Bryant | 2006-07 to 2010-11 |
| Ob | Lukasz Obrzut | 2007-08 to 2007-08 |
| Og | Champ Oguchi | 2010-11 to 2010-11 |
| Yemi Ogunoye | 2008-09 to 2010-11 | |
| Oj | Nkem Ojougboh | 2010-11 to 2010-11 |
| Ok | Augstine Okosun | 2009-10 to 2009-10 |
| Ol | Dean Oliver | 2002-03 to 2002-03 |
| On | Arinze Onuaku | 2010-11 to 2010-11 |
| Or | Randall Orr | 2004-05 to 2005-06 |
| Daniel Orton | 2010-11 to 2010-11 | |
| Os | Eric Osmundson | 2006-07 to 2008-09 |
| Ow | Aaron Owens | 2002-03 to 2002-03 |
| Andre Owens | 2006-07 to 2006-07 | |
| Geoff Owens | 2002-03 to 2003-04 | |
| Kevin Owens | 2003-04 to 2005-06 | |
| Larry Owens | 2009-10 to 2010-11 |