Christopher Plummer admitted that he did the film so he could visit Italy for free. In an interview he said "Give me Rome any day. I'll do porno in Rome, as long as I can get to Rome. Getting to Rome was the greatest thing that happened in that for me."
The filmmakers were highly reluctant to allow John Barry to see the film, in case he decided to quit the project.
New World Pictures producer Roger Corman picked up this film to see if a market existed for low budget space operas. This influenced his decision to go ahead with Battle Beyond the Stars (1980).
David Hasselhoff got food poisoning during shooting so a production assistant in a mask filled in for a significant number of scenes. Hasselhoff also did most of his own stunts. On his first day of stunt work, he accidentally knocked out an Italian stuntman's tooth.
Christopher Plummer was paid $10,000 per day. Most of his scenes as the Emperor of the Galaxy were shot in a single day.