1939–40 League of Ireland
| Season | 1939–40 | 
|---|---|
| Champions | St. James's Gate (2nd title) | 
| Matches played | 132 | 
| Goals scored | 540 (4.09 per match) | 
| Top goalscorer | Patrick Bradshaw (29 goals) | 
← 1938–39  1940–41 →   | |
The 1939–40 League of Ireland was the nineteenth season of the League of Ireland. Shamrock Rovers were the two-time defending champions.
St James's Gate won their second title.