1978 Australian Open – Men's singles
| Men's singles | |
|---|---|
| 1978 Australian Open | |
| Champion | Guillermo Vilas |
| Runner-up | John Marks |
| Score | 6–4, 6–4, 3–6, 6–3 |
| Draw | 64 |
| Seeds | 16 |
Guillermo Vilas defeated John Marks in the final, 6–4, 6–4, 3–6, 6–3 to win the men's singles tennis title at the 1978 Australian Open. It was his first Australian Open title and third major title overall.
Vitas Gerulaitis was the reigning champion, but did not compete this year.
This tournament marked the final major appearance of four-time champion and former world No. 1 Ken Rosewall; he was defeated in the third round by Peter Feigl.