His son Adam confirmed the actor – adored around the world by fans of the show, dubbed Trekkies – died at his home in Los Angeles yesterday morning.
He said the cause of his father’s death was end-stage chronic obstructive pulmonary disease.
Nimoy, who appeared in Star Trek from 1966 to 1969, was loved by fans of the cult TV series for his portrayal of the pointy-eared science officer Mr Spock.
The character was supposed to be half human and half Vulcan, an alien species known for their arid logic.
Nimoy also appeared in big screen versions of the cult series.
The actor left a poignant last message for fans on his Twitter account last Sunday, including a reference to Spock’s famous sign-off, “Live long and prosper”.
The tweet said: “A life is like a garden. Perfect moments can be had, but not preserved, except in memory. LLAP.”
Nimoy was catapulted to fame by the TV series, and became a household name as a result. But his ambivalence towards the role was clear – his two autobiographies were titled I Am Not Spock (1975) and I Am Spock (1995).
In 1954, Nimoy married Sandra Zober, a fellow student at the Pasadena Playhouse, with whom he had two children, Julie and Adam.
But the couple divorced, and in 1988 he married Susan Bay, a film production executive.
Born in Boston to Jewish immigrants from Russia, Nimoy was raised in an Italian section of the city where, although he counted many Italian-Americans as his friends, he said he also felt the sting of antisemitism when growing up.
At age 17 he was cast in a local production of Clifford Odets’ Awake And Sing as the son in a Jewish family.
“This role, the young man surrounded by a hostile and repressive environment, so touched a responsive chord that I decided to make a career of acting,” he said later.
He won a drama scholarship to Boston College but eventually dropped out, moved to California and took acting lessons at the Pasadena Playhouse.
Soon he had lost his “Boston dead-end” accent, hired an agent and began getting small roles in TV series and films.
After service in the US army, he returned to Hollywood, working as a taxi driver, vacuum cleaner salesman, cinema usher and other jobs while looking for acting roles.
Besides wife Susan, son and daughter, Nimoy is survived by his stepson, Aaron Bay Schuck.