Mitchum, who had been suffering from emphysema and was diagnosed with lung cancer last spring, died in his sleep yesterday morning at his home in Santa Barbara, California, his agent, Jack Gilardi, said.
He had been a star for more than half a century, but despite appearing in films like Ryan's Daughter and The Big Sleep as well as countless war dramas and comedies, he never won an Academy award.
"I always thought I had as much inspiration and as much tenderness as anyone else in this business," he said in 1983. "I always thought I could do better. But you don't get to do better, you get to do more."
The actor Edward Fox, who starred with Mitchum in The Big Sleep in 1978, said last night that he was "one of the greatest actors Hollywood has ever known".
"It is tremendously sad to hear of his death. He was an amazing screen actor - one of the greatest actors Hollywood has ever known. He had a hell-raising image, but it was tremendous to work with him. He was a very charming man with a great wit.
"He may not have always made the best films but he was always superb. He had an unbeatable style. He will be greatly missed. He wasn't very old, but he had an amazing life."
Born on 6 August 1917 in Bridgeport, Connecticut, Mitchum led a gypsy- like childhood, frequently moving house and always struggling.
In 1940, he married his high- school sweetheart, Dorothy Spence, and settled down to raising a family and working for a Californian aircraft company. Unhappy there, he signed on as an extra in "pictures", as he always called films. Appearances in Westerns led to bit-parts in a string of "B" movies and two big war films, Cry Havoc and Gung Ho! both released in 1943.
In 1945 Mitchum made the big time as the rugged but weary captain of "The Story of GI Joe", based on the memoirs of war correspondent Ernie Pyle.
But his career faced the danger of crashing in 1948 when he and a starlet named Lila Leeds were arrested on charges of possession of marijuana. He was sentenced to 60 days' jail.
But he emerged from an honour farm with his usual jauntiness: "It's just like Palm Springs without the riffraff."
His rugged good looks, bad- boy image and laconic charm made Mitchum a pin-up for millions of female film-goers, and he was romantically linked with stars including Marilyn Monroe, Ava Gardner and Rita Hayworth.
But he remained modest and described himself as "a hired hand at heart" who rarely watched his own films and famously admitted: "Paint eyeballs on my eyelids and I'll sleepwalk through any picture."
He continued to work well into his 70s, appearing in television dramas when film roles were scarce. He appeared in the epic mini-series The Winds of War and War and Remembrance. He once remarked: "I think when producers have a part that's hard to cast, they say, 'Send for Mitchum; he'll do anything'."
Mitchum added: "I don't care what I play; I'll play Polish gays, women, midgets, anything."
Mr Gilardi said last night: "We've not only lost a great man and a great actor but we've also lost a great friend."Reuse content