Revealing mistake: Right after they "create" Leeloo and she is lying in the plastic cage with the little straps on her, the guy approaches her and says, "if you want out, you are going to have to work on your communication skills." She gives him a dirty look, and then you can see a huge hole, pre-cut in the glass, that she busts her hand through.
Continuity mistake: When the police confront Leeloo on the side of the building, she raises her hands and we can see that they're covered in soot. She jumps off and lands in Korben's cab. When she comes to, she presses her hand against the glass, and her hand is magically clean.
Continuity mistake: When Zorg is first seen walking, and the screen only shows his legs, there is an audible clank as he steps with his RIGHT leg. After that, the clank is heard from his left foot.
Trivia: When the priest states that he has a theory on the advancing planet near the beginning of the film, the president tells him that he has '20 seconds.' Cornelius gives his theory - which takes exactly 20 seconds.
Zorg: A case with four stones in it! Not one or two or three but four! Four stones! What the hell am I supposed to do with an empty case?
Aknot: We are warriors, not merchants.
Zorg: But you can still count. Look it's easy. Look at my fingers, four stones, four crates, zero stones, zero crates! Pack everything up we're outta here.
Aknot: [Mangalores raise their guns.] We risked our lives! I think a little compensation is in order.
Zorg: Oh, so you are merchants after all. Leave them one crate for the cause.
Priest Vito Cornelius: What are you doing?
Korben Dallas: Trying to save your ass so you can save the world.
Leeloo: Leeloo Dallas mul-ti-pass.
Korben Dallas: Yeah.
Korben Dallas: Yeah, multipass, she knows it's a multipass. Leeloo Dallas. This is my wife.
Korben Dallas: We're newlyweds. Just met. You know how it is. We bumped into each other, sparks happen...
Korben Dallas: Yes, she knows it's a multipass. Anyway, we're in love.