MacLeod's nephew, Mark See, told Variety that the actor died early on Saturday. The Hollywood Reporter said that the death was confirmed by Ron Celona, artistic director of the Coachella Valley Repertory.
According to US media reports, MacLeod died in his Palm Desert home. He had been suffering from poor health, but no exact cause of death was given.
Friends, colleagues and fans took to social media to pay tributes.
MacLeod was well-known in the 1970s and 80s thanks to his roles in dozens of TV shows, including "Mary Tyler Moore" and "The Love Boat," as well as several movies.