Richard Dennis Ralston (born July 27, 1942) is an American former professional tennis player whose active career spanned the 1960s and 1970s..

As a young player he was coached by tennis pro Pancho Gonzales. He attended the University of Southern California (USC) and won NCAA championships under their coach, George Toley. He and partner Bill Bond captured the NCAA doubles title in 1964. He was the highest-ranked American player at the end of three consecutive years in the 1960s; Lance Tingay of The Daily Telegraph ranked him as high as World No. 5 in 1966 (Ralston was also ranked World No. 3 by the magazine Reading Eagle in 1963).

His best result at a Grand Slam singles event came in 1966 when he was seeded sixth and reached the final of the Wimbledon Championships which he lost to fourth-seeded Manuel Santana in straight sets. At the end of that year he turned professional.

Ralston was a member of the Handsome Eight, the initial group of players signed to the professional World Championship Tennis tour. He won 27 national doubles and singles titles, including five grand-slam doubles crowns.

Ralston was inducted into the International Tennis Hall of Fame in 1987.