| Competition: | League of Ireland |
| Season: | 1945–46 |
| Winners: | Cork United (5th title) |
| League Topscorer: | Patrick O'Leary (15 goals) |
| Biggest Home Win: | Cork United 9–1 Drumcondra |
| Biggest Away Win: | Bohemians 1–5 Shamrock Rovers Waterford 1–5 Limerick |
| Highest Scoring: | Cork United 9–1 Drumcondra Limerick 4–6 Cork United |
| Matches: | 56 |
| Total Goals: | 258 |
| Prevseason: | 1944–45 |
| Nextseason: | 1946–47 |
The 1945–46 League of Ireland was the 25th season of senior football in the Republic of Ireland.
Cork United were the defending champions.
Brideville failed to get re-elected and were replaced by Waterford, who returned after a five-year absence.
| Team | Location | Stadium | |
|---|---|---|---|
| Bohemians | Dublin (Phibsborough) | Dalymount Park | |
| Cork United | Cork | Mardyke | |
| Drumcondra | Dublin (Clonturk) | Clonturk Park | |
| Dundalk | Dundalk | Oriel Park | |
| Limerick | Limerick | Markets Field | |
| Shamrock Rovers | Dublin (Milltown) | Glenmalure Park | |
| Shelbourne | Dublin (Ringsend) | Shelbourne Park | |
| Waterford | Waterford | Kilcohan Park |
Cork United successfully defended their title, winning their fifth title in six years.
| Rank | Player | Club | Goals |
|---|---|---|---|
| 1 | Patrick O'Leary | Cork United | 15 |
| 2 | Mick O'Flanagan | Bohemians | 11 |
| Tommy McCormack | Drumcondra | ||
| Tommy Eglington | Shamrock Rovers | ||
| 5 | George Sterling | Dundalk | 10 |
| 6 | Benny Henderson | Drumcondra | 8 |
| Paddy Coad | Shamrock Rovers | ||
| Chris Curtin | Waterford | ||
| 9 | Connie Forde | Cork United | 7 |
| Seán McCarthy | |||
| Jackie O'Driscoll | |||
| Willie Fallon | Dundalk | ||
| Tommy Byrne | Limerick | ||
| Davy Cochrane | Shamrock Rovers | ||
| Gerry Malone | Shelbourne | ||
| Leo Ward | Drumcondra | ||