Rafael Nadal defeated the defending champion Alexander Zverev in the final, 6–1, 1–6, 6–3 to win the men's singles tennis title at the 2018 Italian Open. It was his record-extending eighth Italian Open title and his record-extending 32nd Masters title overall. With the win, Nadal also regained the ATP No. 1 singles ranking.
After failing to defend his runner-up points from the previous year, Novak Djokovic fell outside the Top 20 in rankings for the first time since October 2, 2006.
This was the last professional tournament for former world No. 13 Alexandr Dolgopolov. He lost in the first round to Djokovic.
Seeds
The top eight seeds receive a bye into the second round.