Born in Brooklyn, he began his career aged 18 months in his parents’ vaudeville act, Yule and Carter, and never really retired.
By 1965, Mickey Rooney’s 200 films had earned more than $3bn (£1.8bn) around the world.
Sir Laurence Olivier once referred to him as the greatest film actor America ever produced.
Rooney’s death was first reported by US entertainment magazine Variety. The actor is said to have been ill for some time.
In a film and musical career spanning nine decades, Rooney was nominated for four Academy Awards and received two special Oscars, including one in 1983 for his body of work.
Rooney was married eight times, including to screen beauty Ava Gardner .
Asked once if he would marry all his wives again, Rooney replied: “Absolutely. I loved every one of them.”
Initially named Joe Yule Junior, he was barely six years old when he had his first film role as a cigar-smoking midget in Orchids and Ermine.
In 1937, the actor took the part of Andy Hardy in the film A Family Affair. Playing the son of a small-town judge proved a huge box-office draw, and spawned a hit series lasting eight years.
At the same time, a series of barnyard musicals paired him with another celebrated youth star, Judy Garland.
By 1939, Rooney was established as the film industry’s top box office draw.
He enjoyed international triumph alongside Elizabeth Taylor in the 1944 movie National Velvet.
But despite his success, Rooney admitted his fame had forced him to grow up too quickly. By the time he was 30, he said he felt 100 years old.
The show business legend was declared bankrupt by the early 1960s, with much of his money going to alimony for his ex-wives and a reckless lifestyle.
However, his career enjoyed a revival with the film Pete’s Dragon in 1977, and his hit show Sugar Babies which hit Broadway in the late 1970s.
True to his motto to “never retire but inspire”, Rooney continued to work in film, television and theatre well into his 80s.