1912 U.S. National Championships – Men's singles
# 1912 U.S. National Championships – Men's singles

Maurice McLoughlin defeated Wallace F. Johnson 3–6, 2–6, 6–2, 6–4, 6–2 in the final to win the men's singles tennis title at the 1912 U.S. National Championships. The event was held at the Newport Casino in Newport, R.I. in the United States. The challenge round was abolished in this edition, thus requiring all participants, including the defending champion, to play the main draw.

## Draw

### Finals

| Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final | Final | Final |
| - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - | - |
| R. Norris Williams | 4 | 7 | 4 | 6 | 3 | | | | | | | | | | | |
| Maurice McLoughlin | 6 | 5 | 7 | 3 | 6 | | | | | | | | | | | |
| Maurice McLoughlin | 6 | 5 | 7 | 3 | 6 | Maurice McLoughlin | 8 | 6 | 3 | 6 | | | | | | |
| | | | | | | William Clothier | 6 | 2 | 6 | 4 | | | | | | |
| William Clothier | 7 | 6 | 6 | | | William Clothier | 6 | 2 | 6 | 4 | | | | | | |
| Raymond Little | 5 | 0 | 1 | | | | | | | | | | | | | |
| Raymond Little | 5 | 0 | 1 | | | | | | | | Maurice McLoughlin | 3 | 2 | 7 | 6 | 6 |
| | | | | | | | | | | | Wallace F. Johnson | 6 | 6 | 2 | 4 | 2 |
| George Church | 2 | 2 | 0 | | | | | | | | | | | | | | Wallace F. Johnson | 6 | 6 | 2 | 4 | 2 |
| Karl Behr | 6 | 6 | 6 | | | | | | | | | | | | | |
| Karl Behr | 6 | 6 | 6 | | | Karl Behr | 6 | 0 | 3 | 2 | | | | | | |
| | | | | | | Wallace F. Johnson | 4 | 6 | 6 | 6 | | | | | | |
| Wallace F. Johnson | 8 | 8 | 3 | 6 | | Wallace F. Johnson | 4 | 6 | 6 | 6 | | | | | | |
| Watson Washburn | 6 | 2 | 6 | 3 | | | | | | | | | | | | |
