The 1990 International Championships of Spain, also known as the Spanish Open, was a tennis tournament played on outdoor clay courts at the Real Club de Tenis Barcelona in Barcelona, Spain that was part of the Tier IV category of the 1990 WTA Tour.

It was the ninth edition of the tournament and was held from 23 April until 29 April 1990.

Second-seeded Arantxa Sánchez won the singles title and earned $27,000 first-prize money as well as 190 ranking points.

[1] Arantxa Sánchez defeated Isabel Cueto 6–4, 6–2 Mercedes Paz / Arantxa Sánchez defeated Sabrina Goleš / Patricia Tarabini 6–7(7–9), 6–2, 6–1