The 79-year-old star - who is most famous for the role of Spock in the `Star Trek` TV show and movies - says he will not appear in the next `Star Trek` movie and will take a back seat so Zachary Quinto, who took over the character in 2009, can continue in the role.
He said: "I`ve been doing this professionally for 60 years. I love the idea of going out on a positive note. I`ve had a great, great time.
"I want to get off the stage. Also, I don`t think it would be fair to Zachary Quinto. He`s a terrific actor, he looks the part, and it`s time to give him some space. And I`m very flattered the character will continue."
Despite his retirementfromacting, Nimoy admits he is grateful he got to revive the role of the Vulcan first officer in `Star Trek`.
He told the Toronto Sun newspaper: "Since JJ Abrams revived the `Star Trek` franchise, I felt I owed him something. And I`m glad I did it because he promised me a good story, and it was."
Recently Zachary promised he would attempt to get Nimoy to come back to the sequel to the movie.
He said: "I think I might have to ask him this time. Every time JJ calls I pick up in a heartbeat. I assure you that. And when it`s to tell me to come to work I`ll be there."