Nikola Mektic is a Croatian tennis player specializing in doubles, of which he was number 1 in the ATP ranking for the first time in October 2021.

Since 2021 he has played together with his compatriot Mate Pavic, with whom he won the 2021 Wimbledon Tournament and the Tokyo Olympics. He won another 20 tournaments on the major circuit, including the 2020 ATP Finals paired with Wesley Koolhof, with whom he also reached the final at the 2020 US Open, and 7 ATP Tour Masters 1000 rounds.

He also won the mixed doubles tournament at the 2020 Australian Open partnering Barbora Krejcikova. Since 2011 he has been part of the Croatian Davis Cup team, with which he won the 2018 edition and reached the final in the 2020-2021 edition. Since 2017 he plays almost exclusively in doubles.