Ken Rosewall defeated Lew Hoad 4–6, 6–2, 6–3, 6–3 in the final to win the men's singles tennis title at the 1956 U.S. National Championships.

[2] Hoad was attempting to complete the Grand Slam.

The seeded players are listed below.

Ken Rosewall is the champion; others show the round in which they were eliminated.