Trivia about Planet Hulk.
- The Marvel comic characters Star Lord, the Grand Master, Adam Warlock, Gamora and Pip the Troll all appear in the crowd or behind the Red King in the arena where Hulk fights throughout the film.
- In the original comic, Hulk's third opponent in the arena was Silver Surfer. This was changed to Beta Ray Bill due to Silver Surfer's rights being unavailable at the time of production and the crew thought the hammer-wielding Beta Ray Bill would make a better fit on a gladiator world.
- As in the original comic, Korg's flashback to his fight with Thor is taken from Thor's first appearance in "Journey Into Mystery" #89. The only change from the original story is Beta Ray Bill appearing and helping Thor.
- Throughout the movie, Hulk does not revert to Bruce Banner despite being either knocked out or in a calm state. Writer Greg Johnson offers the explanation that Sakarr's atmosphere is toxic to humans and so Hulk cannot change back or else he will die as Banner. Director Sam Liu, on the other hand, states that the cosmic rays that flooded Hulk's ship before crashing on Sakarr might have altered him in some way.