Joe Kubert, a titan among comic-book artists whose work stretched from the Golden Age of the superhero to the gritty realism of the graphic novel, died on Sunday in Morristown, N.J. He was 85.

The cause was multiple myeloma, his son Adam said.

Mr. Kubert, who first plied his trade as a teenager in the 1930s and continued drawing in the hospital during his final illness, was among the last of the generation of comic-book illustrators whose work helped define the genre in the years before World War II.

“He’s the longest-lived continuously important contributor to the field,” Paul Levitz, a former president of DC Comics, said in an interview on Monday. “There are two or three of the greats left, but he’s definitely one of the last.”