1966 U.S. National Championships – Men's singles

Unseeded Fred Stolle defeated John Newcombe 4–6, 12–10, 6–3, 6–4 in the final to win the men's singles tennis title at the 1966 U.S. National Championships.

Seeds
The seeded players are listed below. Fred Stolle is the champion; others show the round in which they were eliminated.


 * 1) 🇪🇸 Manuel Santana (semifinals)
 * 2) 🇦🇺 Roy Emerson (semifinals)
 * 3) 🇺🇸 Dennis Ralston (fourth round)
 * 4) 🇦🇺 Tony Roche (third round)
 * 5) 🇺🇸 Arthur Ashe (third round)
 * 6) Cliff Drysdale (third round)
 * 7) 🇺🇸 Clark Graebner (quarterfinals)
 * 8) 🇺🇸 Cliff Richey (second round)

Key

 * Q = Qualifier
 * WC = Wild card
 * LL = Lucky loser
 * r = Retired