1990 Athens Open

The 1990 ATP Athens Open was a men's tennis tournament played on outdoor clay courts in Athens in Greece that was part of the World Series of the 1990 ATP Tour. It was held from 1 October through 7 October 1990. Seventh-seeded Mark Koevermans won the singles title.

Singles
Mark Koevermans defeated 🇦🇷 Franco Davín 5–7, 6–4, 6–1
 * It was Koevermans' only singles title of his career.

Doubles
🇪🇸 Sergio Casal / 🇪🇸 Javier Sánchez defeated Tom Kempers /  Richard Krajicek 6–4, 6–3
 * It was Casal's 7th title of the year and the 32nd of his career. It was Sánchez's 4th title of the year and the 10th of his career.