Lucio Fulci's cut of the film was approximately 70 minutes, before he had to leave the production due to a stroke. Producer Franco Gaudenzi asked second unit director Bruno Mattei and writer Claudio Fragasso to take over the director's chair. They cut Fulci's footage down to around 50 minutes and added 40 minutes of their own.
In the original script, the skull which flies out of the freezer was not included - it was added by Lucio Fulci. He later remarked that he felt it was one of the most clever things he had come up with, and was the only thing about the movie he was truly proud of.
Like many Italian movies shot for the international market, most of the cast delivered their lines in English and were then re-dubbed for the US release anyway. Only a few members of the cast actually spoke Italian.
Blue Heart's supposed radio set list (briefly seen in the shot where his sunglasses are sitting on the desk in front of him) is in fact just a piece of printed paper with only "Play Beatles Song" written on it in red pen.
For years after Zombie 3 (1988) was released, fans from the UK had been hoping that Lucio Fulci would make a true sequel to Zombie Flesh Eaters - the UK title for Zombie (1979) - and Fulci expressed a great interest in making a "Zombie Flesh Eaters Part 2" to atone for Zombie 3 (1988), but sadly the project never came to light.