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.
See main article: 1999 Monte Carlo Open – Singles. Gustavo Kuerten defeated Marcelo Ríos, 6–4, 2–1, retired
See main article: 1999 Monte Carlo Open – Doubles. Olivier Delaître / Tim Henman defeated Jiří Novák / David Rikl, 6–2, 6–3