Infobox last updated on: April 7, 2007.

Ilie Năstase (born July 19, 1946, in Bucharest, Romania) is a former Romanian professional tennis player, one of the world's top players of the 1970s. Năstase was the World No. 1 in 1973 according to the Association of Tennis Professionals ranking system, which placed him first from August 23, 1973 to June 2, 1974. He is one of the five players in the world to win more than 100 pro titles in singles (57) and doubles (51). He was inducted into the International Tennis Hall of Fame in 1991. Năstase won seven Grand Slam titles: two in singles, three in men's doubles, and two in mixed doubles. He also won four Tennis Masters Cup championships. In 2005, Tennis magazine ranked him as the 28th-best player of the preceding forty years.

At the beginning of his career in 1966 Năstase travelled around the world competing with his good friend Ion Ţiriac. Together, they represented Romania in the Davis Cup competition, being three times runners up: in 1969, 1971 and 1972.