| 1940 Waterford Senior Hurling Championship | |
| Champions: | Mount Sion |
| Count: | 3 |
| Runners-Up: | Dungarvan |
| Previous Year: | 1939 |
| Previous Tournament: | 1939 Waterford Senior Hurling Championship |
| Next Year: | 1941 |
| Next Tournament: | 1941 Waterford Senior Hurling Championship |
The 1940 Waterford Senior Hurling Championship was the 40th staging of the Waterford Senior Hurling Championship since its establishment by the Waterford County Board in 1897.
Mount Sion were the defending champions.
On 8 December 1940, Mount Sion won the championship after a 6–05 to 3–02 defeat of Dungarvan in a replay of the final.[1] This was their third ever championship title and their third title in succession.