| Competition: | Irish League |
| Season: | 1904–05 |
| Winners: | Glentoran 3rd Irish title |
| Matches: | 56 |
| Total Goals: | 136 |
| Prevseason: | 1903–04 |
| Nextseason: | 1905–06 |
The 1904–05 Irish League was the 15th edition of the Irish League, the highest level of league competition in Irish football.
The league comprised 8 teams, and Glentoran won the championship after winning a play-off with Belfast Celtic by a score of 3–1.