Nunnally Johnson, 79, screenwriter, newspaper columnist and motion picture director whose films included "The Man in the Gray Flannel Suit," "The Grapes of Wrath," and "The Three Faces of Eve," died Friday at Good Samaritan Hospital in Los Angeles of pneumonia.

Mr. Johnson considered the highest paid writer in Hollywood during the 1940s, worked with 20-Century-Fox, United Artists, Metro-Goldwyn-Mayer and Paramount Pictures. He retired in 1967, after writing the screenplay for "The Dirty Dozen."

Mr. Johnson also wrote a book of short stories in 1930 titled, "There Ought to be a Law." A newspaper columnist with Brooklyn Eagle, The New York Post and PM, Mr. Johnson also wrote stories for the Saturday Evening Post before going to Hollywood.

Mr. JOhnson began as a reporter at 16. He had starred as first baseman on his high school baseball team in Columbus, Ga., but decided against making baseball his career because "he feared he wouldn't make the big leagues," according to his son-in-law Michael Lonergon.

After working for the Columbus Enquirer Sun for a year he quit because his pay was too low and wet to work in a factory. But a year later he returned to reporting, writing for the Savannah (Ga.) Evening Press.

Three months later, however, Mr. Johnson joined the Georgia Hussars, a cavalry unit, and went off to the Mexican border war. He remained in the Army throughout World War I.

In 1919,he joined the New York Tribune as a reporter and covered several beats before going to the Brooklyn Eagle as a columnist.

He returned to the Tribune to cover the Scopes "Monkey Trial" in 1925.

Mr. Johnson then quit the Tribune to write a column for the New York Post and wrote short stories for the Saturday Evening Post, Smart Set, and American Mercury.

He did so well writing frot he magazines that he devised a scheme to force himself to quit newspapering and write fiction on a full-time basis.

"He went into the editor's office at the Post and asked for double his salary," said his son-in-law, knowing full well he'd never get it. So he quit."

Mr. Johnson then went to Hollywood, after being offered a job as a "junior scenarist" by Herman Mankiewicz of Paramont Pictures. He quit that job after six weeks and returned to New York where he wrote more short stories and traveled.

The next year he returned to Hollywood, joining the newly organized 20th Century Company and wrote his first successful script, "Moulin Rouge."

Beginning in 1934, Mr. Johnson distinguished himself by writing the screenplays for three box office hits: "The House of Rothschild," "Bulldog Drummond Strikes Back," and "Kid Millions."

After writing the scenario for "Thanks a Million," Mr. Johnson signed a contract with Darryl Zanuck of 20th Centry as an assistant producer.

As an assistant producer, he worked on "The Man who Broke The Bank," in 1935; "The Prisoner of Shark Island," "The Country Doctor," and "Banjo on My Knee," all in 1936.

He later wrote the screenplays for "Grapes of Wrath," "Holy Matrimony," "The Gunfighter," "The Mud Lark," "The Desert Fox," and "How to Marry a Millionaire."

Mr. Johnson received praise for his work on "Grapes of Wrath." According to "Current Biography," Mr. Johnson "transcribed the script more faithfully than most critics had thought possible."

"The story line was clear," he said, "and as old as the Bible - the migration of a people forced from their homes."

After this success, Mr. Johnson wrote the screenplays for "Chad Hanna," "Wife, Husband and Friend," "Rose of Washington Square," "I was an Adventurist," and "Tobacco Road."

Mr. Johnson professed to dislike writing a screenplay without also being the film's producer.

"The nice thing about it," he said, "is that once I'm hired as the producer I can go out on a lot where a director is kicking my script around and say, 'Listen, what we want you to do is make this picture the way it's written here on this papuh.' Jus' you stick to this papuh.'"

The Southern accent came from Mr. Johnson's Southern upbringing.

Mr. Johnson produced, directed and wrote the screenplays for four films, "Night People," "Black Widow," "Oh Men, Oh Women," and "The Three Faces of Eve."

He did the screenplay for and directed "The Man in The Gray Flannel Suit."

He is survived by five children, Marjorie Flowler, of Beverly Hills, Calif.; Nora Johnson, of New York City; Christie Johnson of Los Angeles, Scott Johnson of New York, and Roxanna Lonergon, of Beverly Hills.