| Election Name: | 1940 United States Senate election in Massachusetts |
| Country: | Massachusetts |
| Flag Year: | 1908 |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 1934 United States Senate election in Massachusetts |
| Previous Year: | 1934 |
| Next Election: | 1946 United States Senate election in Massachusetts |
| Next Year: | 1946 |
| Election Date: | November 5, 1940 |
| Image1: | File:Sen. David I. Walsh 1939 (cropped).jpg |
| Nominee1: | David I. Walsh |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 1,088,838 |
| Percentage1: | 55.64% |
| Nominee2: | Henry Parkman Jr. |
| Party2: | Republican Party (United States) |
| Popular Vote2: | 838,122 |
| Percentage2: | 42.38% |
| Map Size: | 250px |
| Senator | |
| Before Election: | David I. Walsh |
| Before Party: | Democratic Party (United States) |
| After Election: | David I. Walsh |
| After Party: | Democratic Party (United States) |
The 1940 United States Senate election in Massachusetts was held on November 5, 1940, with Democratic incumbent David I. Walsh defeating his challengers.
Senator Walsh was unopposed for renomination.
Parkman was unopposed for the Republican nomination.