The 1999 Monte Carlo Open was a 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 April 19 through April 25, 1999.
Gustavo Kuerten def. Marcelo Ríos, 6–4, 2–1, ret.
- 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.
Olivier Delaître / Tim Henman def. Jiří Novák / David Rikl, 6–2, 6–3