2004 Adidas International – Men's singles

Hyung-Taik Lee was the defending champion but did not compete that year.

Lleyton Hewitt won the final 4–3 after Carlos Moyá was forced to retire.

Seeds
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated.


 * 1) 🇪🇸 Juan Carlos Ferrero (first round)
 * 2) 🇩🇪 Rainer Schüttler (first round)
 * 3) 🇪🇸 Carlos Moyá (final)
 * 4) 🇦🇺 Mark Philippoussis (quarterfinals)
 * 5) 🇹🇭 Paradorn Srichaphan (second round)
 * 6)  Nicolás Massú (first round)
 * 7) 🇦🇺 Lleyton Hewitt (champion)
 * 8)  Martin Verkerk (semifinals)