Continuity mistake: After the villain (Thayer David) kills a duck, a boulder begins to move and brushes the side of his right leg as seen in a close-up and both legs can squarely be seen as he is standing beside the rock. The scene changes to a stunt-man who has his left-side towards the camera and this time his right leg is closer to the boulder which pushes him over a ledge. (01:50:35)
Continuity mistake: In the beginning Professor Lindenbrook places his mountain goat horned ink well out of the way behind some scales, any other scene after that, they are missing.
Continuity mistake: James Mason meets the villain (Thayer David) who holds a gun on Mason and the rest. Mason outwits him by throwing salt into his face to blind him. When the salt hits his face, he closes his eyes (too early) before impact. The salt impact hits the right side of his face. An angle change occurs and we see a close-up of him (or a stunt double - his hair is different) and the salt hits the actor squarely in his face with his eyes open to the last microsecond. The scene changes back to show Mason and the villain with the salt on the right-side of the villain's face again with him in agony. (01:24:20)
Continuity mistake: After the professor makes his speech at the end, he is talking to Carla. He puts his hand to his chin then puts it down. It cuts and his hand is up again.
Continuity mistake: When Professor Lindenbrook is on the ladder in his study there appears to be a mirror reflecting a fire above the fire place. When the rectors come in there is a picture above the fireplace.
Continuity mistake: At the explosion in the lab, Jenny is blown on top of a desk with straight lines down the side. Nowhere prior or after shots is there any such desk. The next shot, Alec is picking her up from the floor.
Continuity mistake: When they are in the sunken city, the haversack is put down on a rock with a hammer on top of it. In a later scene, the hammer handle is pointing in a different direction.
Continuity mistake: When they are climbing up out of the hole to avoid the rising water in the cave, as they show the hole from below the water is about two feet below the hole, however when shown from the top the water looks to be about six inches below the hole, this keeps shifting back and forth during that scene.
Continuity mistake: Pat Boone was shot in the right arm by the villain. After a few scenes, his wound is gone - no evidence of an injury. (01:34:05)
Continuity mistake: Arlene Dahl trips while running away from a dinosaur by stepping into a loop in a rope attached to a raft. Her foot snags it below the ankle near her toes. A few seconds later, you see a close-up of her and the dinosaur and now the rope is above her ankle. A few scenes later it's below her ankle again as the men come to her rescue. (01:42:10)
Continuity mistake: Before the explosion in the lab, James Mason has his gloves, after the explosion he has to crawl around the desk only to find his gloves laying on the floor. Extra set?
Continuity mistake: When madam breaks the stalactite during the flood, there is a small hole which grows wider and smoother as the team evacuates.
