With cooperation from the US Air Force and Texas Air National Guard, producer Robert Clarke filmed at Fort Worth's Carswell Air Force Base and the abandoned Marine Corps Air Station at Eagle Mountain Lake. The badly deteriorated buildings were used to show that the air base from which he took off was in ruins.

The was shot at the same time as Edgar G. Ulmer's The Amazing Transparent Man (1960). The combined shooting time for the double feature was only two weeks. This film was also meant to cash in the popularity of George Pal's The Time Machine (1960).

The "X-80" is played by a Convair F-102 Delta Dagger, first introduced into service in 1956.

This film and another Robert Clarke / Edgar G. Ulmer production, The Amazing Transparent Man (1960), which was shot at the same time and in the same location, were originally to be distributed by a company called Pacific International. Shortly after the films were completed, Pacific International went bankrupt, and producer Clarke lost all the money he had put into it. The films were put up for auction by the film lab that processed them in order to recoup its costs. Both films were bought by American-International Pictures for a fraction of their cost, and upon release they made the company quite a bit of money. Except for his salary as an actor for two weeks' work, Clarke never saw a dime from the films.

Some of the sound effects are taken from George Pal's The War of the Worlds (1953).

Screenwriter Arthur C. Pierce appears briefly as one of the mutants escaping from the jail cell in the underground citadel.

Although the "X-80" is actually a Convair F-102 Delta Dagger in most scenes, a few stock footage shots show an F-106 Delta Dart. The most notable difference is the shape of the vertical stabilizer, the upper portion of which is flat rather than pointed. Also, the air intakes on the F-106 are located well behind the cockpit rather than at the front of the cockpit as on the F-102.

Vladimir Sokoloff, who played "The Supreme" in this movie, played "the old man" in "The Magnificent 7" which was also released in 1960. Although he played a Mexican in "The Magnificent 7," he was actually from Russia and his Russian accent can be heard in "Beyond The Time Barrier."

The film takes place in 1960 and 2024.