Continuity mistake: After Leon rescues Mathilda from the SWAT team and dodges the snipers, he shoots out a ventilation fan to make an escape route. He gets off two shots before we see the vent, but when it does we see about 7 bullet holes around the vent. Then the camera goes back to Leon as he continues firing. When the camera switches back, the holes around the vent are different. (01:27:05)
Continuity mistake: Before the dreadlocked man starts looking at the vinyl records in the apartment, he places his uzi down with the butt facing the camera. In the next shot the barrel is facing the camera, and switches back again in the next shot.
Continuity mistake: In the scene where Mathilda returns to her apartment and takes the hidden stash of money out from the loose floor board, she leaves the board open and also takes the money out of the plastic bag and leaves the bag on the floor too. In the next shot, the camera angle switches to her looking down the hall because she hears people coming. When the camera switches back to the original angle of her scurrying away, the floor board is back in place and she's wrapped the money back up in the plastic - nowhere near enough time to do that. (01:02:25)
Continuity mistake: When Mathilda spends her first night at Leon's apartment, Leon places a messily folded blanket on her in one shot. The camera then goes to a different shot of Leon, and then back to the original. However, we can now see that the blanket is mostly unfolded and placed neatly on Mathilda. ..... (and little pink doll she is holding changes position). (00:37:15)