Continuity mistake: When Jay and Tee first start to talk to Jeff, Tee grabs the "weed." When Jeff gets mad and starts banging on the grate, the wide shot shows Tee in the same position, gripping Jeff's weed, however it was not digitally added in that shot, so he's gripping nothing. But in the next shot, he's shown gripping the weed again.
Continuity mistake: Throughout the whole movie when someone is driving they keep driving to different locations but if you look out the window it's just the same green background all the time. (02:27:09)
Continuity mistake: The entrance room (the large stone building off Battery Avenue) to the starport reverses between the two movies. In the first movie, the guard sits on the right hand wall as one faces the elevator, with a fan visible through a grille behind him, and a circular vent on the other wall. In MiB II, he is sitting against the left hand wall, but the fan and grille is still behind him, meaning it has changed walls. (00:17:15)