The 1955–56 season was the 41st in the history of the Isthmian League, an English football competition.
Wycombe Wanderers were champions, winning their first Isthmian League title.
| Competition: | Isthmian League |
| Season: | 1955–56 |
| Winners: | Wycombe Wanderers |
| Matches: | 210 |
| Total Goals: | 794 |
| Prevseason: | 1954–55 |
| Nextseason: | 1956–57 |