| Champ: |  Sebastian Korda |
| Runner: | Tseng Chun-hsin |
| Score: | 7–6(8–6), 6–4 |
See main article: 2018 Australian Open.
Sebastian Korda, the son of 1998 men's singles champion Petr Korda, won the boys' singles tennis title at the 2018 Australian Open, defeating Tseng Chun-hsin in the final, 7–6(8–6), 6–4.
Zsombor Piros was the defending champion, but was no longer eligible to participate in junior events. He received a wildcard into the men's singles qualifying competition, where he lost to Bjorn Fratangelo in the second round.