| Election Name: | 1938 United States Senate election in Washington |
| Country: | Washington |
| Type: | presidential |
| Ongoing: | no |
| Previous Election: | 1932 United States Senate election in Washington |
| Previous Year: | 1932 |
| Next Election: | 1944 United States Senate election in Washington |
| Next Year: | 1944 |
| Election Date: | November 8, 1938 |
| Nominee1: | Homer Bone |
| Party1: | Democratic Party (United States) |
| Popular Vote1: | 371,535 |
| Percentage1: | 62.62% |
| Nominee2: | Ewing D. Colvin |
| Party2: | Republican Party (United States) |
| Popular Vote2: | 220,204 |
| Percentage2: | 37.12% |
| Map Size: | 275px |
| U.S. Senator | |
| Before Election: | Homer Bone |
| Before Party: | Democratic Party (United States) |
| After Election: | Homer Bone |
| After Party: | Democratic Party (United States) |
The 1938 United States Senate election in Washington was held on November 8, 1938. Incumbent Democratic U.S. Senator Homer Bone was re-elected to a second term in office over Republican Ewing D. Colvin.
The blanket primary was held on September 13, 1938.