The 2003 Adidas International was a combined men's and women's tennis tournament played on outdoor hard courts at the NSW Tennis Centre in Sydney in Australia that was part of the International Series of the 2003 ATP Tour and of Tier II of the 2003 WTA Tour. The tournament ran from 5 through 12 January 2003. Lee Hyung-taik and Kim Clijsters won the singles titles.
| 2003 Adidas International | |
|---|---|
| Date | 5–12 January |
| Edition | 111th |
| Surface | Hard / outdoor |
| Location | Sydney, Australia |
| Venue | NSW Tennis Centre |
| Champions | |
| Men's singles | |
 Lee Hyung-taik | |
| Women's singles | |
 Kim Clijsters | |
| Men's doubles | |
 Paul Hanley / Nathan Healey | |
| Women's doubles | |
Kim Clijsters /  Ai Sugiyama | |
Finals
editMen's singles
edit Lee Hyung-taik defeated 
Juan Carlos Ferrero 4–6, 7–6(8–6), 7–6(7–4)
- It was Lee's 1st title of the year and the 1st of his career.
Women's singles
edit Kim Clijsters defeated 
Lindsay Davenport 6–4, 6–3
- It was Clijsters' 1st title of the year and the 15th of her career.
Men's doubles
edit Paul Hanley / Nathan Healey defeated 
Mahesh Bhupathi / Joshua Eagle 7–6(7–3), 6–4
- It was Hanley's 1st title of the year and the 2nd of his career. It was Healey's only title of the year and the 2nd of his career.
Women's doubles
edit Kim Clijsters / Ai Sugiyama defeated Conchita Martínez / Rennae Stubbs 6–3, 6–3
- It was Clijsters' 2nd title of the year and the 16th of her career. It was Sugiyama's 1st title of the year and the 25th of her career.