2009 Monte-Carlo Rolex Masters

The 2009 Monte-Carlo Rolex Masters, a tennis tournament for male professional players, was played from April 11 through April 19, 2009, on outdoor clay courts. It was the 103rd edition of the annual Monte Carlo Masters tournament, which was sponsored by Rolex for the first time and was classified as an ATP World Tour Masters 1000 tournament on the 2009 ATP World Tour. It took place at the Monte Carlo Country Club in Roquebrune-Cap-Martin, France, near Monte Carlo, Monaco.

Except for Andy Roddick, all the top ranked male tennis players participated. World No. 2 Roger Federer had initially decided not to participate in this tournament but changed his mind and accepted a wild-card invitation to play. World No. 1 Rafael Nadal achieved a record fifth straight title at this particular event (the first to win five consecutives titles in any Masters tournament).

The 2009 Monte Carlo Masters tournament is the only one of the nine "Masters 1000" events scheduled for that year without a mandatory player commitment. In 2007, the Association of Tennis Professionals had decided to make participation in the eight newly rebranded "Masters 1000" compulsory for all top players. The tournaments in Monte Carlo and Hamburg were originally due to be removed from the top tier of events; however, the tournament directors filed lawsuits, and Monte Carlo was allowed to remain a top tier event while Hamburg became a 500 Series event.