The 2018 Miami Open presented by Itaú (also known as 2018 Miami Masters) was a professional men and women's tennis tournament played on outdoor hard courts.

All men and women's events took place at the Tennis Center at Crandon Park in Key Biscayne, Florida, United States, from March 19 through April 1, 2018.

It was the last time the tournament was played at the Tennis Center at Crandon Park.

The tournament moved to the Hard Rock Stadium starting in 2019.

† Ramos Viñolas is entitled to use an exemption to skip the tournament and substitute his 18th best result (45 points) in its stead.