Mervyn LeRoy, 86, the producer and director who made some of America's most popular and best remembered movies, including "The Wizard of Oz," "Mr. Roberts" and "Little Caesar" during an Oscar-winning career behind the camera that spanned five decades, died yesterday at his home in Beverly Hills.

Mr. LeRoy, who began movie work in the silent era and became a director with the advent of sound, showed a sure touch on films of virtually every type and genre from the lavishly spectacular "Quo Vadis" to the grittily realistic "I Am a Fugitive From a Chain Gang." He was a success with comedy and romance, musical and melodrama.

It was Mr. LeRoy who introduced Ronald Reagan, then a Hollywood star, to a young actress named Nancy Davis, who eventually became his wife.

"Mervyn LeRoy was a special part of our lives," the Reagans said yesterday in a statement. They said they "always referred to him as our Cupid," and called him "always a precious friend."

In addition, the Reagans characterized Mr. LeRoy as "one of the pillars of the entertainment industry, responsible for some of the finest motion pictures ever," adding that he knew "just what to say to get his actors to make it right."

Mr. LeRoy, the producer or director of more than 75 films, including "Random Harvest" and "Waterloo Bridge," had been bedridden for months. He was found dead in his bed yesterday about 8 a.m. by his wife Kathryn, who attributed his death to natural causes. He had a heart problem.

Mrs. LeRoy called her husband "a dear sweet man whom everybody loved," and told United Press International that "I'm happy to say he had very few problems in his life."

Among Mr. LeRoy's Hollywood achievements was the discovery in 1937 of Lana Turner, who he said was brought to see him by Zeppo Marx, a member of the famed comedy team, who was then acting as an agent. Mr. LeRoy starred her in "They Won't Forget."

Although Mr. LeRoy's account destroys the cherished myth according to which Miss Turner was discovered on a stool in Schwab's drugstore, the start of his own career appears to epitomize the Hollywood legend.

He was born Oct. 15, 1900, in San Francisco to an importer-exporter whose prosperous business was destroyed in the 1906 earthquake and fire. After his father died when he was 10, he began selling newspapers on the street.

His post was outside the Alcazar theater, and almost inevitably, he was discovered by a power in the theatrical world and hired in 1912 to play the part of a newsboy in a movie.

In succeeding years, he worked as a movie extra, found his way into vaudeville as "The Boy Tenor of This Generation," got a job from a cousin folding costumes for a movie studio, played juvenile roles in films, served as an assistant cameraman, and in 1924 became a gag writer.

In 1927, he directed his first movie, "No Place to Go." Three years later he directed Edward G. Robinson in "Little Caesar," the prototypical Hollywood gangster film.

Through the 1930s, he directed many of the fast-paced melodramas that gave the Warner Bros. studio a reputation for films embodying hard-grained social realism.

Later in that decade, while continuing to work as a director, Mr. LeRoy also began producing movies, including, in 1939, "The Wizard of Oz." In 1938, he went to work as a producer and director for MGM, and in 1944, he started a production company of his own.

Films he produced or directed in the 1940s included "Thirty Seconds Over Tokyo," "Little Women," "Blossoms in the Dust" and "Madame Curie."

In 1945 he made "The House I Live In," starring Frank Sinatra. Mr. LeRoy's first documentary, it won a special Academy Award.

His career continued to flourish through the 1950s and '60s as he produced such films as "East Side, West Side," "Quo Vadis" and "Million Dollar Mermaid." He produced and directed "The FBI Story," "No Time for Sergeants," "Gypsy" and "Mary, Mary."

He received Hollywood's Irving Thalberg career achievement award in 1975.

In the 1950s, when the film industry seemed to be foundering, Mr. LeRoy made this observation: "Our business was built on 'moving' pictures. But too many sit and talk and talk. That's what's wrong with so many movies today."

He had two children, Warner and Linda, by his marriage to Doris Warner, a member of the film family. Their marriage ended in divorce. Warner LeRoy, a restaurant impresario, opened the Potomac Restaurant in the Washington Harbour development. Mr. LeRoy and his wife Kathryn were married in 1946.