See main article: article and 2003 MasterCard German Open.
Defending champion Justine Henin-Hardenne defeated Kim Clijsters in the final, 6–4, 4–6, 7–5 to win the singles tennis title at the 2003 WTA German Open. It was her third title of the year, and the ninth of her career.
The first nine seeds received a bye into the second round.