| Men's Singles | |
|---|---|
| 1978 U.S. Clay Court Championships | |
| Champion |
|
| Runner-up |
|
| Final score | 7–2, 6–1 |
Manuel Orantes was the defending champion but lost in the semifinals to Jimmy Connors. Top-seed Connors claimed the title and first prize money of $24,000 by defeating seventh-seeded José Higueras in the final.
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.