S. J. Perelman, American humorist who continually touched both the joy and the persecution psychosis of the ordinary American, died yesterday in New York at the age of 75.

The great solemn, thick-spectacled comic writer (Mr. Perelman preferred "comic writer" to the term humorist) died of natural causes at his home in the Gramercy Park Hotel, according to a spokesman for the New York City medical examiner.

As early as 1929, Mr. Perelman was publishing zany and uncommon pieces, starting with "Dawn Ginzburg's Revenge," which was a collection of humorous pieces.

Millions first encountered him through the Marx Brothers, for Mr. Perelman was one of the writers for "Horsefeathers" and "Monkey Business."

Over the years he worked in many forms, including travel books that blended facts and eccentricities and projects of inner megalomania and tenderness and no telling what all else.

And then, year after felicitous year, he wrote for The New Yorker, which still has some of his unpublished pieces, and which published a Perelman story as recently as Sept. 10.

He was born in Brooklyn and thought as a youth it would be nice to be a cartoonist. He used to draw figures on cardboard strips in his father's dry goods store.

but as he matured, he was seduced by language. He was educated at Brown University, where he edited the college humor magazine and wrote editorials. Then he not only survived but flourished in 11 years of work in Hollywood.

For some writers it is said Hollywood was a low point in their lives, but not for Mr. Perelman, who not only did well there, but emerged as fresh as an April colt, unspoiled by any balderdash there may have been in the film capital. He won an Oscar in 1956 when he returned to Hollywood with "Around the World in 80 Days."

Not long before his death he had regretfully abandoned his tour of China in a convertible sports car after he caught pneumonia.

Mr. Perelman's brand of humor was uncommon. He had no great use for the sharp whip-like gag line, and did not specialize in the gentle brooding way of humorists who reflect on the follies of the world.

On the contrary, Mr. Perelman's characters were themselves foibles, and, not to split hairs, largely crazy. He often cast a character as "I," which gave him great freedom to be as zany as he liked.

He would explain, in some humorous piece, that he scratched his ankle. He would then scream about gushing wounds and the approach of death and the frightful danger of poisons being administered to him. The reader gradually figured out, as the piece went along, that he had scratched an ankle and a lady was applying a little mercurochrome or something. s

He always saw trifling events and casual comments as if they were the Battle of Lepanto or King Richard II yielding his crown to a thug.

While other humorists tried to reduce humor to something limpid, organic, inevitable and profoundly true, Mr. Perelman marched the other way and vaulted from one incredible exaggeration to the next. He understated nothing. He squeezed the last blood from every turnip and then some. The result was, against all rules and probabilities, enchanting.

In person he was fastidious in dress, almost ceremonious in manner, and a purist in both grammar and pronunciation. If he ever used clumsy constructions in speech, most people who talked with him never heard them.

Unlike his books, which dealt largely with characters of heroic egocentricity, he loved to put himself down, in face-to-face conversations. Not seriously, of course. But he snorted if anyone tried to work him around to the philosophical and moral implications of humor. He plied his trade as a comic, and that was all.

Of course nobody ever believed his oft-stated judgment about the low estate of his task as humorist. The polish of his conversational rhythms, the near-Byzantine luxuriance of allusions (he assumed his readers had read everything) and the firmness of his tangents, all reflected the disciplined artist, not the crazy amateur.

Mr. Perelman appeared to think the world was nuts, and proposed to enjoy his (all too short) stay in it, and to share any delight he happened to find with anybody who chose to read him.

He loved not only the texture of words the rich piling on of sounds and far-fetched allusions, but loved words for themselves. A typical sample from a Marx Brothers film:

"Jennings is waxing wroth outside." And the reply:

"Well, tell Wroth to wax Jennings for a while."

He loved puns. He loved learning. He loved riding through China in a convertible sports car. He leaves his son, Adam, and his daughter, Abby.