| Player | Position | Last Season | Birthdate | Country |
| O'Regan, Thomas | C | 1985-1986 | 12/29/1961 | USA |
| O'Reilly, Cal | C | 2011-2012 | 09/30/1986 | CAN |
| Odelein, Lyle | D | 2005-2006 | 07/21/1968 | CAN |
| Oksiuta, Roman | R | 1996-1997 | 08/21/1970 | RUS |
| Olausson, Fredrik | D | 2002-2003 | 10/05/1966 | SWE |
| Olczyk, Eddie | R | 1999-2000 | 08/16/1966 | USA |
| Oliwa, Krzysztof | L | 2005-2006 | 04/12/1973 | POL |
| Orpik, Brooks | D | 2012-2013 | 09/26/1980 | USA |
| Ouellet, Michel | R | 2008-2009 | 03/05/1982 | CAN |
| Owchar, Dennis | D | 1979-1980 | 03/28/1953 | CAN |