Continuity mistake: You'll notice that they put a lot of emphasis on the sun rising and "showing the way." The sun then rises IN FRONT of them. When the camera gives us a view of the riders on the camels, the shadows from their hats fall directly on their faces, when instead there should be no shadows. When the camera moves to show them all riding towards Humanaptra, their shadows fall a little to the left and behind, like it's high noon or something. (01:37:45)
Continuity mistake: When Benny is looking for the black book in the office, he gets caught by O'Connell. When they are standing under the fan, you hear the scream of the Egyptologist. They all look towards the camera but when Benny runs out the window behind them, the Egyptologist is there. (01:18:40)
Continuity mistake: When Henderson shoots the burning guy to save Jonathan, I counted at least ten shots from his pistol. Also happens when Rick shoots, he seems to fire off more than the 12 shots you would think he'd be limited to.
Continuity mistake: The pharaoh realises that his mistress Anck Su Namun was touched by another man because the body paint on her left shoulder is smudged. However, the way it is messed up differs drastically between when it was being smudged by Imhotep and when the pharaoh points to it. (00:02:40)
Continuity mistake: When everyone jumps off the burning river boat it is heading away from them, but in the next shot the boat is just starting to pass everyone while they are reaching the shore.
Continuity mistake: When Imhotep takes Benny as his servant, he holds out some gold items in a very skeletal hand (where he had the gold when he had no pockets is another matter). When O'Connell and friends are leaving Hamanoptera, Imhotep's hand comes out of the sand. You can see that it is either a prop hand, or a crewman's hand in a glove, as it is thicker than it was a few moments before.
Continuity mistake: At the beginning of the movie when Evie is putting the books back, she is standing on the ladder leaning against the bookshelf and the top rung of the ladder is at mid thigh. When she reaches and the ladder stands up the top rung is at breast level. (00:13:00)
Continuity mistake: In the scene where Imhotep's sarcophagus first falls through the ceiling Jonathon is practicing his golf swing a few feet away from Rick and Evie. When the sarcophagus falls exactly where Jonathon has been standing, Jonathon is suddenly 20 feet away without having had a chance to move.
Continuity mistake: In the scene where the group is waiting on Evie to decipher where the black book is, Jonathan runs out to get the car and it's pointing one way. When everyone runs out to get in the car, it's now pointing on the opposite direction. There's no way he could've turned the car around that fast.