2003 BMW Open – Singles

Younes El Aynaoui was the defending champion but did not compete that year.

Roger Federer won in the final 6–1, 6–4 against Jarkko Nieminen. He did not lose a single set in the entire tournament.

Seeds

 * 1)  Roger Federer (champion)
 * 2) 🇹🇭 Paradorn Srichaphan (second round)
 * 3)  Sjeng Schalken (quarterfinals)
 * 4) 🇩🇪 Rainer Schüttler (quarterfinals)
 * 5) 🇷🇺 Yevgeny Kafelnikov (semifinals, retired because of a neck injury)
 * 6) 🇷🇺 Mikhail Youzhny (quarterfinals)
 * 7) 🇬🇧 Tim Henman (second round)
 * 8) 🇫🇮 Jarkko Nieminen (final)