From The Grindhouse Cinema Database
- During special effects work on the film, the stop-motion animation crew used their brontosaurus model and miniature jungle set to film a shot for The Twilight Zone: The Odyssey of Flight 33 (1961).
- Marcel Delgado was given less than half the time originally agreed upon to create the dinosaur models used in the film. The studio initially agreed to give him five to six weeks, as he requested, but two weeks later he was told that they would begin production on Tuesday.
- Originally, it was intended for Steve McQueen to star in this film, after he had appeared in The Blob (1958) from the same producer and director. However, McQueen had been so difficult to work with, that they didn't even bother.
- Dinosaur footage from this film was used on several episodes of It's About Time (1966).
- The roar of the Tyrannosaurus would be re-used many times in later movies and TV shows.
- In 1960, Universal Pictures distributed this film on a double bill with SOS Pacific (1959).
- The comic book that O'Leary is reading while keeping an eye on the frozen dinosaurs is "Rip Van Winkle in the 21st Century", which may be a movie prop and not an actual comic book. Rip Van Winkle is mentioned in the film near the end of the movie.
- When the lightning strikes the dinosaurs, re-awakening them, the security guard left to watch them can be seen reading a comic book version of "Rip Van Winkle", the story of a man who fell asleep, only to wake up 20 years later.