Leonard died at home in the Detroit suburb of Bloomfield Township surrounded by his family, according to a message on his website. He had suffered a stroke several weeks ago and had been hospitalized in the Detroit area.
He didn't have a best-seller until "Glitz" when he was 60 in 1985, but every novel from then was a best-seller. He helped achieve for crime writing what Stephen King did for horror and Ray Bradbury for science fiction.
Leonard wrote 45 novels total, on top of a number of short stories and essays, and more than 20 of his pieces were adapted into films or television shows, including the current FX show "Justified."
When the movie version of "Get Shorty" premiered in 1995 starring John Travolta, Leonard became the darling of Hollywood's hottest young directors.
Quentin Tarantino took a turn with "Rum Punch," turning it into "Jackie Brown," a campy, Blaxploitation-style film starring Pam Grier. But Steven Soderbergh stayed faithful to Leonard's story and dialogue with "Out of Sight."
"People always say, 'Where do you get (your characters') words?' And I say, 'Can't you remember people talking or think up people talking in your head?' That's all it is. I don't know why that seems such a wonder to people," he told The Associated Press last year.
Last fall, Leonard became the first crime writer to receive an honorary National Book Award, a prize given in the past to Philip Roth, Norman Mailer and Arthur Miller.
The Library of America, which publishes hardcover editions of classic American writing, is planning a three-volume set of his work.
Leonard, who married Beverly Cline in 1949, leaves behind five children, 12 grandchildren and five great grandchildren.
The Associated Press and ABC News contributed to this report.