| Boys' Singles | |
|---|---|
| 1999 US Open | |
| Champion |
|
| Runner-up |
|
| Final score | 6–7, 6–3, 6–4 |
David Nalbandian was the defending champion, but did not compete this year.
Finnish player Jarkko Nieminen defeated Danish first seed Kristian Pless in the all-Scandinavian final, 6–7, 6–3, 6–4.