John R. Fischetti, 64, a Pulitzer Prize-winning cartoonist with the Chicago Sun-Times and the Field Newspaper Syndicate, died Tuesday in a hospital in Chicago. He had a heart ailment.

Mr. Fischetti received a Pulitzer Prize for editorial cartooning in 1969.

He also was the recipient of the National Headliners Club medal, two awards from Sigma Delta Chi society of professional journalists, and four consecutive awards from the National Cartoonists Society.

He will probably be best remembered in his profession as the artist who popularized the horizontal, black on white cartoon that used gray tones. Before Mr. Fischetti's cartoons became widely known, the most common cartoon was the stark black on white, vertical cartoon.

Upon learning of the artist's death, Herbert Block, The Washington Post's editorial cartoonist, said that Mr. Fischetti was "a hell of a cartoonist, a hell of a guy and a great friend."

In an autobiographical work, "Zinga, Zinga, Zinga, Za," published in 1973, the late Peter Lisagor, Washington bureau chief of the Chicago Daily News, said of cartoonists in general and John Feschetti in particular, that their work "falls somewhere between ancient hieroglyphics and contemporary graffiti, without being as sacred as the first or as profane as the second. With a few deft scratches, a curved line here and a drooping one there, a jowl swollen with greed or an eye leaking malice, they somehow manage to say funny and profound things."

Mr. Fischetti was born in Brooklyn and attented Pratt Institute. He served in the Army during World War II, and described his war duty as landing in France and then "digging foxholes to Paris."

He began drawing cartoons for Walt Disney in Burbank, Calif., and began his newspaper career with the old Chicago Sun in 1941. During and after the war he had contributed cartoons to Punch magazine in England. He worked for the old New York Herald Tribune for 10 years and the Newspaper Enterprise Association for eight years before joining the old Chicago Daily News in 1967. He worked for the Daily News until joining the Chicago Sun-times in 1978.

Mr. Fischetti is survived by his wife, Karen, and two sons. CAPTION: Illustration, This cartoon was one of Mr. Fischetti's favorites. It helped him win Pulitzer Prize. By John Fischetti; copyright (c) 1968 for The Chicago Daily News; Picture, John R. Fischetti