Mario Tennis, known in Japan as Mario Tennis 64 (マリオテニス64 Mario Tenisu Rokujūyon), is a 2000 sports video game developed by Camelot Software Planning and published by Nintendo for the Nintendo 64 video game console. The game was released in North America and Japan in the summer of 2000, and released in Europe later in November. It is the first tennis-based game starring Mario since Mario's Tennis, and the second game developed by Camelot on a Nintendo system. The game is known for being the introduction of Luigi's evil doppleganger, Waluigi, and the re-introduction of Princess Daisy and Birdo.

Mario Tennis was re-released on the Wii Virtual Console in 2010 and on the Wii U Virtual Console in 2015. The game's success led to four sequels: Mario Power Tennis released for the Nintendo GameCube in 2004, Mario Tennis Open released for the Nintendo 3DS in 2012, Mario Tennis: Ultra Smash released for the Wii U in 2015 and Mario Tennis Aces which will release for the Nintendo Switch in 2018.