Fred Dekker did uncredited re-writes on the script. When he was brought on, the script began in the future and Spartan was introduced when he was brought out of suspended animation. Dekker suggested that this movie open with a prologue set in 1996 to showcase Spartan and Phoenix in their natural environment, saying that "If you don't show Kansas, Oz isn't all that special."
Sylvester Stallone described the cryogenic freezing scene as "probably the worst five hours I've ever had on movie sets... I was terrified."
Wesley Snipes' kicks and punches sometimes look lurchy and awkward. Snipes is an accomplished black belt in real life, and his kicks and punches were so fast that they blurred on-camera. Hence the producers asked him to slow them down.
Wesley Snipes hated his blond dye job, and shaved his head as soon as filming was complete. After this movie's release, professional NBA player Dennis Rodman began dying his hair different colors, a look that was inspired by Simon Phoenix.
Sylvester Stallone wanted Simon Phoenix to be played by Jackie Chan. Chan declined the offer since Asian audiences give negative feedback on the idea of action stars from either Hong Kong or Hollywood who have always played heroes, all of a sudden become type-casted as villains.
Dan Cortese: first, he is seen playing the piano and singing at Taco Bell. Later, he can be seen briefly as one of the cryo-prison guards helping Simon Phoenix thaw out criminals with Associate Bob before the final fight.