Continuity mistake: In the plaza scene where Zorro first appears. His horse is initially followed by many wildly barking small dogs. As he rounds the final corner and confronts the soliers, the dogs have suddenly vanished.
Continuity mistake: In the climactic sword fight between Power and Rathbone, the Captain hand Diego a sword and they immediately start a classic duel. At end, Diego pulls off a dueling glove that he had never put on.