| 1990 Estoril Open | |
|---|---|
| Date | 2–8 April (men) 16–22 July (women) |
| Edition | 1st(ATP) / 2nd(WTA) |
| Category | ATP World Series (men) Tier V (women) |
| Draw | 32S/16D |
| Prize money | $225,000 (men) $100,000 (women) |
| Surface | Clay / outdoor |
| Location | Oeiras, Portugal |
| Venue | Estoril Court Central |
| Champions | |
| Men's singles | |
 Emilio Sánchez | |
| Women's singles | |
 Federica Bonsignori | |
| Men's doubles | |
| Sergio Casal / Emilio Sánchez | |
| Women's doubles | |
Sandra Cecchini /  Patricia Tarabini | |
The 1990 Estoril Open was a combined men's and women's tennis tournament played on outdoor red clay courts. It was the first edition of the event Estoril Open for men (the 2nd for women), and was part of the ATP World Series of the 1990 ATP Tour. It took place at the Estoril Court Central, in Oeiras, Portugal, from 2 April through 8 April 1990 for the men's tournament and from 16 July through 22 July 1990 for the women's tournament. Emilio Sánchez and Federica Bonsignori won the singles titles.
