Spanish-born filmmaker Luis Bunuel, whose surrealistic movies often mocked middle-class mores and won him honors the world over during a 60-year career, died here today of a liver ailment. He was 83.

Mr. Bunuel, a pioneer director regarded by many critics as among the world's greatest, was known for movies that often were designed to shock the viewer.

Some of his films drew strong reaction from church groups opposed to his portrayals of sexual fetishes, inexplicable violence and jabs at what he regarded as the hypocrisy of religion.

Mr. Bunuel, hospitalized for the last week in intensive care, left Spain because of the 1936-39 civil war. He lived for a time in the United States and then moved to Mexico and became a citizen in 1949. He made 20 of his 32 movies in this country.

He lived in a middle-class Mexico City neighborhood with his French wife of 50 years, Jeanne.

Born to well-to-do landowners Feb. 22, 1900, in Calanda, Spain, he studied at the University of Madrid, where he met Salvador Dali. Over three days, the two wrote a surrealistic film script that became the classic, 24-minute "Un Chien Andalou."

The film, known in English as "An Andalusian Dog," consisted of a series of unrelated images designed simply for their shock effect. One image was that of a razor slashing across an eyeball.

The movie, which is occasionally seen here in revivals and remains the subject of heated discourse at filmmaking seminars the world over, catapulted both Dali and Mr. Bunuel into the forefront of the surreal art movement in Paris in the 1920s.

Of those years in Paris half a century ago, he later wrote: "Devoured by some dreams as big as the Earth, we were nothing, nothing more than a group of insolent intellectuals that blustered in a cafe and published a magazine."

At first he was surprised at the reaction his early films provoked from most of his audience. In his memoir, "My Last Sigh," published last winter, Mr. Bunuel recalled seeing one of his movies advertised in Paris as being by "the cruelest movie director in the world." He called this "a stupidity that made me very sad."

Mr. Bunuel also directed the masterpiece "L'Age d'or" "The Golden Age" in 1930, which attacked the Catholic Church and middle-class morality--a theme exhibited in virtually all his later films. These included included "The Young and the Damned," "The Great Madcap," "Simon of the Desert," "Tristana," "The Phantom of Liberty," "The Exterminating Angel," "The Discreet Charm of the Bourgeosie," and his final work, "That Obscure Object of Desire."

"Discreet Charm," a film made in 1972, won the Academy Award for best foreign film. His screenplay "Viridiana" was cowinner of the grand prize of the Cannes Film Festival in 1961.

His most popular success in this country, however, was probably "Belle de Jour," featuring French actress Catherine Deneuve as a wealthy married woman who becomes a prostitute out of boredom.

"They call Bunuel everything: traitor, anarchist, pervert, defamer, iconoclast. But lunatic they do not call him," said Henry Miller when "L'Age d'or" opened. "It is true, it is lunacy he portrays," Miller said, "but it is not his lunacy . . . this is the lunacy of civilization, the record of man's achievement after 10,000 years of refinement."

Last February on his birthday, Mexican President Miguel de la Madrid and Alberto Isaac, the head of the Cinemagraphic Institute, visited Mr. Bunuel to express their admiration for his talent.

In his recent memoir he wrote, "I can establish my diagnosis easily. I'm old. That's my principal illness. I only feel good in my house, loyal to my daily routine."

The book was published in French and Spanish and an English edition recently appeared. In it, he said he had weak eyes and a severe hearing problem that left him unable to listen to the music he loved.

He hated publicity and maintained a secluded, sedate lifestyle during his last years, rarely going out or speaking publicly.

He is survived by his wife and two sons, Rafael, a professor who lives in San Francisco, and Juan Luis, a film director who lives in Paris.