A Spanish-language version was shot back-to-back with the English-language version.
The beast was animated using two separate stop-motion animation methods. A two-foot-high armatured, rubber-covered model was moved, exposing a frame at a time. Also utilized was replacement animation, a technique that involved several different models of the same character made of plaster, each slightly different to represent a particular action. When filmed in sequence for a few frames per second, the illusion of motion is achieved. The breathing effect of the creature was accomplished by pumping air in small increments into a cavity of the throat of the two-foot-high model and then releasing it in the same manner. When seen on the screen the throat rises and falls creating the breathing effect. Two large rubber feet were filmed for the shots of the monster walking, which were worn as shoes by a technician.
The first feature film to combine stop-motion animation with anamorphic Cinemascope and color.
Willis H. O'Brien was originally to have also provided the special effects for the film.
Six actors from The Beast of Hollow Mountain have appeared in two films together. Carlos Rivas, Mario Navarro, Pascual Garcia Pena, Jose Chavez, Roberto Contreras, and Margarito Luna have also appeared in The Black Scorpion.
The beast is barely mentioned throughout the film and, except for a shadow at 0:44, isn't seen until 0:59 in the film.
This film has sometimes been claimed to be a remake of Willis O'Brien's pioneering 1919 stop-motion short "The Ghost of Slumber Mountain," but the two have nothing in common except that both end with a hero being chased by a flesh-eating dinosaur.