The Monte Carlo Masters is an annual tennis tournament for male professional players held in Roquebrune-Cap-Martin, France, a commune that borders on Monte Carlo, Monaco. The event is part of the ATP Masters Series on the Association of Tennis Professionals (ATP) Tour. The tournament is played on clay courts. It is currently held every year in the April-May period. Prior to the establishment of the Tennis Masters Series in the early-1990s, the event was known as the Monte Carlo Open.
The Monte Carlo tennis championship was first held in 1897. It became an "Open" event in 1969.