Troy Donahue (born Merle Johnson Jr., January 27, 1936 – September 2, 2001) was an American film and television actor and singer. He was a popular sex symbol in the 1950s and 1960s.

His father was Merle Johnson, the manager of the motion-picture department of General Motors. His mother, Edith Johnson, was a retired stage actress. Donahue attended a New York military academy, where he met Francis Ford Coppola. When Donahue was 18, he moved to New York and got a job as a messenger in a film company founded by his father. He was fired, he says, because he was too young to join the union. He attended Columbia University and studied journalism. He trained briefly with Ezra Stone, and then moved to Hollywood.

The big break of Donahue's career came when he was cast opposite Sandra Dee in A Summer Place, made by Warner Bros. in 1959. The director was Delmer Daves. Warner signed him to a long-term contract. They put him to work guest-starring in episodes of their Western TV series, such as Colt .45 (1959), Maverick (1959), Sugarfoot (1959), The Alaskans (1960), and Lawman (1960).

In 1968, Donahue signed a long-term contract with Universal Studios for films and TV. This lasted a year and saw him get four roles: guest shots on Ironside (1968), The Name of the Game (1968), and The Virginian (1969), and an appearance in the TV movie The Lonely Profession (1969).

Donahue declared bankruptcy in 1968 and eventually lost his home. In 1969, Donahue moved from Los Angeles to New York City. By this time, Donahue's drug addiction and alcoholism had ruined him financially. In May 1982, he joined Alcoholics Anonymous, which he credited for helping him achieve and maintain sobriety.

Donahue continued to act in films throughout the 1980s and into the late 1990s. Donahue's final film role was in the 2000 comedy film The Boys Behind the Desk, directed by Sally Kirkland.

On August 30, 2001, Donahue suffered a heart attack and was admitted to Saint John's Health Center in Santa Monica. He died three days later, on September 2, at the age of 65.