Continuity mistake: When everyone is running out of the theater, a woman with a red belt and yellow purse can be seen exiting with the other terrified patrons. A few seconds later, the exact same woman is seen running out of the theater again.
Continuity mistake: In the final sequence where Dracula's foot has been disintegrated by the rays of the sun, his foot is seen firmly attached again seconds later as Van Helsing confronts him with a makeshift cross. In the scene Cushing, with his back to the camera, steps forward quickly from the foreground to cover the area where Lee's foot is briefly seen as having not been disintegrated.
Continuity mistake: The interior of the ship is quite spacious, a central atrium on each level, with crew quarters and storage spaces opening off it. Yet, when the two officers take a space-walk down the length of the ship, it appears to have a diameter of less than 20 feet.
Continuity mistake: When the old man who left town sees the spider return to the cave, it is dark outside. He returns to town to report, and it is daylight outside. The sheriff and his men leave immediately, but when they get to the cave it is dark outside once more. The cave is not so far from town that it takes a day to travel the distance.