1999 Estoril Open – Men's singles

Alberto Berasategui was the defending champion, but lost in the first round this year.

Albert Costa won the tournament, beating Todd Martin in the final, 7–6(7–4), 2–6, 6–3.

Seeds
• # 🇷🇺 Yevgeny Kafelnikov (first round)

• # 🇺🇸 Todd Martin (final)

• # Marcelo Ríos (semifinals)

• # 🇪🇸 Albert Costa (champion)

• # 🇧🇷 Gustavo Kuerten (quarterfinals)

• # 🇪🇸 Félix Mantilla (quarterfinals)

• # 🇪🇸 Francisco Clavet (first round)

• # 🇷🇺 Marat Safin (first round)