1990 ATP German Open – Singles

Juan Aguilera defeated Boris Becker in the final, 6–1, 6–0, 7–6(9–7) to win the singles tennis title at the 1990 Hamburg European Open.

Ivan Lendl was the reigning champion, but did not compete this year.

Seeds
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated. The top eight seeds received a bye to the second round. • # Boris Becker (final)

• # 🇺🇸 Andre Agassi (third round)

• # 🇺🇸 Aaron Krickstein (third round)

• # 🇪🇸 Emilio Sánchez (third round)

• # 🇺🇸 Jay Berger (quarterfinals)

• # 🇪🇨 Andrés Gómez (second round)

• # 🇺🇸 Michael Chang (second round)

• # Andrei Cherkasov (withdrew)

• # 🇦🇷 Martín Jaite (first round)

• # 🇺🇸 Jim Courier (third round)

• # Carl-Uwe Steeb (second round)

• # 🇦🇹 Thomas Muster (withdrew)

• # 🇦🇹 Horst Skoff (first round)

• # 🇦🇷 Guillermo Pérez Roldán (first round)

• # 🇸🇪 Magnus Gustafsson (quarterfinals)

• # 🇦🇷 Alberto Mancini (first round)