1999 Monte Carlo Open

The 1999 Monte Carlo Open was a men's tennis tournament played on outdoor clay courts. It was the 93rd edition of the Monte Carlo Open, and was part of the ATP Super 9 of the 1999 ATP Tour. It took place at the Monte Carlo Country Club in Roquebrune-Cap-Martin, France, near Monte Carlo, Monaco, from 19 April through 25 April 1999.

Thirteenth-seeded Gustavo Kuerten won the singles title.

Singles
🇧🇷 Gustavo Kuerten defeated 🇨🇱 Marcelo Ríos, 6–4, 2–1, retired
 * It was Gustavo Kuerten's 1st title of the year, and his 4th overall. It was his 1st Masters title of the year, and overall.

Doubles
🇫🇷 Olivier Delaître / 🇬🇧 Tim Henman defeated 🇨🇿 Jiří Novák / 🇨🇿 David Rikl, 6–2, 6–3