Tous les députés dont le nom commence par: o
| Oakley, George | Riverdale |
| O'Connor, Hamilton Parke | Bruce-Sud |
| O'Connor, Lawrence | Durham--York |
| O'Connor, Terrance P. | Oakville |
| O'Donoghue, Daniel John | Ottawa |
| O'Donoghue, Daniel John | Ottawa |
| Offer, Steven | Mississauga-Nord |
| O'Keefe, George O. | Ottawa (2 sièges) |
| Oke, Leslie Warner | Lambton-Est |
| Olde, Neil Leverne | Middlesex-Sud |
| Oliver, Adam | Oxford-Sud |
| Oliver, Adam | Oxford-Sud |
| Oliver, Farquhar Robert | Grey-Sud |
| O'Neil, Hugh Patrick | Quinte |
| O'Neill, John | Toronto-Sud-Est - siège A |
| O'Neill, Yvonne | Ottawa--Rideau |
| Orazietti, David | Sault Ste. Marie |
| Ostrom, Gilbert Wellington | Hastings-Ouest |
| O'Sullivan, John C. | Peterborough-Est |
| O'Toole, John | Durham |
| Ouellette, Jerry J. | Oshawa |
| Overall, Cyril Arthur Goodwin | Niagara Falls |
| Owen, Bruce | Simcoe-Centre |
| Owens, Edward William James | Toronto-Sud-Est - siège B |
| Owens, Stephen David | Scarborough-Centre |