1999 Grand Prix de Tennis de Lyon – Singles

Àlex Corretja was the defending champion, but lost in the second round this year.

Nicolás Lapentti won the title, defeating Lleyton Hewitt, 6–3, 6–2 in the final.

Seeds
• # 🇷🇺 Yevgeny Kafelnikov (quarterfinals)

• # 🇺🇸 Todd Martin (second round)

• # 🇧🇷 Gustavo Kuerten (quarterfinals)

• # 🇪🇸 Àlex Corretja (second round)

• # 🇩🇪 Tommy Haas (second round)

• # 🇪🇨 Nicolás Lapentti (champion)

• # 🇫🇷 Cédric Pioline (second round)

• # 🇺🇸 Vincent Spadea (semifinals)

• # 🇦🇺 Mark Philippoussis (second round)

• # 🇪🇸 Albert Costa (second round, retired)

• # 🇦🇷 Mariano Zabaleta (third round)

• # 🇫🇷 Sébastien Grosjean (third round)

• # 🇦🇺 Lleyton Hewitt (final)

• # 🇺🇦 Andrei Medvedev (second round)

• # 🇷🇺 Marat Safin (second round)

• # Marc Rosset (second round)