1938 U.S. National Championships – Men's singles
| Men's singles | |
|---|---|
| 1938 U.S. National Championships | |
| Champion | Don Budge |
| Runner-up | Gene Mako |
| Score | 6–3, 6–8, 6–2, 6–1 |
Don Budge defeated Gene Mako in the final, 6–3, 6–8, 6–2, 6–1 to win the men's singles tennis title at the 1938 U.S. National Championships. He became the first player in tennis history to complete the Grand Slam.