Continuity mistake: Right before Axel shoots Zack at the mansion, there is a large vase behind Axel. When he shoots Zack however, the vase disappears. There are bullet holes in the wall where the vase was, implying Zack fired his gun at Axel. But Zack never fires his gun, so the vase simply vanishes from the scene. (01:32:00)
Continuity mistake: At the end shoot out in the house, Foley and Taggart bump into each other and a henchman shoots the grass near them with a submachine gun, ripping up the grass. Billy shoots the assailant and they come out from behind the wall - the grass that was shot up is in pristine condition, with no bullet holes or damage whatsoever. (01:28:15)
Continuity mistake: When Axel Foley hits Victor's hitman in the restaurant and the hitman lands on the buffet table, he has lots of stuff on his face and something green is stuck on his forehead. In the next shot, the hitman's face has been cleaned up a little and the green thing stuck on his forehead disappears.
Other mistake: When Maitland shoots Axel in his house, he has a large calibre hand gun. The shot was in Axel's right arm, just below the shoulder, apparently straight on, as only one hole is seen. The hole was way too small for the size gun and should have easily penetrated into his lungs making it difficult for Axel to breathe. It also would have damaged the bone in his arm making it impossible for him to use it.