| 2004 Ontario Men's Curling Championship | |
| Host City: | Owen Sound, Ontario |
| Arena: | Harry Lumley Bayshore Community Centre |
| Dates: | February 2–8 |
| Winner: | Team Harris |
| Curling Club: | Oakville CC, Oakville, Ontario |
| Skip: | Mike Harris |
| Third: | John Base |
| Second: | Phil Loevenmark |
| Lead: | Trevor Wall |
| Prev: | 2003 |
| Next: | 2005 |
The 2004 Ontario Men's Curling Championship was held February 2–8 at the Harry Lumley Bayshore Community Centre in Owen Sound.
1998 Olympic silver medallist Mike Harris and his team of John Base, Phil Loevenmark and Trevor Wall would go on to win his lone provincial championship of his career. They would go on to represent Ontario at the 2004 Nokia Brier in Saskatoon.
This would mark the final provincial championship for 2-time World champion and 56-year-old Ed Werenich who had come out of retirement for the season.
| Skip | Third | Second | Lead | |
|---|---|---|---|---|
| Trevor Wall | ||||
| Jason Mitchell | ||||
| Chris Lumbard | ||||
| Ken McDermot | ||||
| Al Hutchinson | Peter Irwin | |||
| John Steski | ||||
| Doug Gibson | Alex Faulkner | |||
| Graham Allan | Jim Collings | |||
| Lino Di Iorio | ||||
| Darcy Tomchick | Jake Higgs |
| Skip | Club | Wins | Losses | |
|---|---|---|---|---|
| 7 | 2 | |||
| 7 | 2 | |||
| 5 | 4 | |||
| 5 | 4 | |||
| 5 | 4 | |||
| 4 | 5 | |||
| 4 | 5 | |||
| 4 | 5 | |||
| 3 | 6 | |||
| 1 | 8 |