The movie was originally to be filmed on location in New York City in Technicolor with James Dean in the lead role. However, after Dean's sudden death and replacement by Paul Newman, it was decided the film should be in black and white, and filmed on studio sets. Director Robert Wise felt the sets looked fake, and only used them for night scenes, while filming the daytime scenes on location.
There had been some opposition to the casting of Paul Newman, since at 31 he was already six years older than James Dean would have been, and his first movie The Silver Chalice (1954) had been a critical and commercial disaster.
Eileen Heckart, who played "Ma Barbella", was only six years older than Paul Newman, who played Rocky Barbella. She was born in 1919 and he was born in 1925.
Paul Newman trained hard for the role with the help of Tony Zale. He trained so hard that Zale stopped toying with him and hit him for good. Zale explained later that he had to show who the boss was between him and Newman.