Continuity mistake: Near the end, banditos murder Fred C. Dobbs and leave his stripped body by the waterhole as they go chasing after the burros, which they later try to sell in town. Within hours, Howard and Bob Curtin ride right past the same waterhole on their way to town, but Fred Dobbs' body is nowhere to be seen.
Continuity mistake: In the opening scenes, the Red Witch has her lee rail almost awash, yet the view on deck and in the cabin following, the vessel is perfectly upright.
Continuity mistake: As he eats, a bread chunk rests on the table to the right of Oliver's bowl. As he rises, the bread is gone. (00:14:20 - 00:14:50)