| Competition: | Liga Mayor |
| Season: | 1942–43 |
| Winners: | Marte (2nd title) |
| Matches: | 56 |
| Total Goals: | 278 |
| League Topscorer: | Manuel Alonso (17 goals) |
| Prevseason: | 1941–42 |
| Nextseason: | 1943–44 |
The 1942-43 season was the edition XXI of the league's amateur era called Liga Mayor. It was the last edition before the first professional and true national league was started in 1943.