2018 French Open – Men's singles

Defending champion Rafael Nadal defeated Dominic Thiem in the final, 6–4, 6–3, 6–2 to win the men's singles tennis title at the 2018 French Open. It was his record-extending eleventh French Open title and 17th major title overall. Nadal equaled Margaret Court's all-time record of eleven singles titles won at one major, and was the first player to achieve the feat in the Open Era. He retained the world No. 1 singles ranking with the victory; Roger Federer (despite not playing the clay court season) was also in contention for the top position.

Novak Djokovic was attempting to become the first man in the Open Era to achieve a double career Grand Slam, but he lost in the quarterfinals to Marco Cecchinato. Thiem was the first Austrian to reach a major singles final since Thomas Muster at the 1995 French Open.

With Alexander Zverev as the second seed, this was the first time since the 2006 Australian Open that a player outside of the Big Four was one of the top two seeds at a major.

Cecchinato, ranked as the world No. 72 and having failed to win a main draw match in his four previous appearances, was the first unseeded men's singles semifinalist at the French Open since Gaël Monfils in 2008, the lowest-ranked man to reach the semifinals since Andriy Medvedev in 1999, and the first Italian man to reach a major singles semifinal since Corrado Barazzutti at the 1978 French Open.