The 1989 Estoril Ladies Open was a tennis tournament in Portugal. They took place from July 17 to July 23, 1989 on the clay court tennis facility of the Complexo Desportivo do Jamor in Oeiras . It was the first edition of this tournament and part of the WTA Tour as a Tier V tournament .
In the individual, the German Isabel Cueto prevailed in the final against the Italian Sandra Cecchini in two sets. For Cueto it was the fourth title of her career and the first success in 1989.