| 1940 All-Ireland Minor Football Championship | |
| Bodyclass: | vevent |
| Headerstyle: | background:#BFD7FF; |
| Labelstyle: | white-space: nowrap |
| Datastyle: | white-space: nowrap |
| Header1: | Championship details |
| Label2: | Dates |
| Label3: | Teams |
| Header4: | All-Ireland Champions |
| Label5: | Winning team |
| Data5: | Louth (2nd win) |
| Label6: | Captain |
| Label7: | Manager |
| Header8: | All-Ireland Finalists |
| Label9: | Losing team |
| Data9: | Mayo |
| Label10: | Captain |
| Label11: | Manager |
| Header12: | Provincial Champions |
| Label13: | Munster |
| Data13: | Kerry |
| Label14: | Leinster |
| Data14: | Louth |
| Label15: | Ulster |
| Data15: | Monaghan |
| Label16: | Connacht |
| Data16: | Mayo |
The 1940 All-Ireland Minor Football Championship was the 12th staging of the All-Ireland Minor Football Championship, the Gaelic Athletic Association's premier inter-county Gaelic football tournament for boys under the age of 18.
Roscommon entered the championship as defending champions, however, they were defeated in the Connacht Championship.
On 22 September 1940, Louth won the championship following a 5–05 to 2–07 defeat of Mayo in the All-Ireland final. This was their second All-Ireland title and their first in four championship seasons.[1]
Final
Final (Croke Park, Dublin)
| GK | 1 | Colm Browne (Cooley Kickhams) |
| RCB | 2 | Brendan Breen (Ardee minors) |
| FB | 3 | Brendan Burke (St. Mary's College) (c) |
| LCB | 4 | Kevin Flanagan (Ramblers) |
| RHB | 5 | Benny Fretwell (Cooley Kickhams) |
| CHB | 6 | Ned Reay (St Magdalene's) |
| LHB | 7 | Oliver Mohan (Ardee minors) |
| MF | 8 | Larry Murphy (Dowdallshill) |
| MF | 9 | Paddy Kelly (Ardee minors) |
| RHF | 10 | Gus Cahill (St. Mary's College) |
| CHF | 11 | Séamie McGivern (Ardee minors) |
| LHF | 12 | Peter Corr (Seán O'Mahony's) |
| RCF | 13 | Phil McCourt (Castlebellingham) |
| FF | 14 | Jackie Kiernan (St Magdalene's) |
| LCF | 15 | George Brennan (Lann Léire) |
Final
Final
Semi-Finals
Final (Croke Park, Dublin)
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