Continuity mistake: In the final final fight scene, Jean Claude's hair is dry and combed, then wet and sweaty, then back to dry so on and so forth.
Factual error: In a flashback to his youth, one of the bullies is wearing a Bartles and James T-shirt, which is a product that didn't exist in the early 70's.
Factual error: The film was made in 1988. At that time the airport was on the mainland Kowloon side and called Kai Tak. In the early part of the film where van Damme is heading for the "East Lake Hotel" in Kowloon he is seen riding on an electric tram. These trams are only found on Hong Kong Island, which means he would have had to have crossed the harbour to reach the trams and then gone back across the harbour to reach his hotel. Fairly pointless exercise.
Continuity mistake: When Frank and Jackson first meet Mr.Lin in the hotel he has a little moustache, goatee, and some sideburns, as much as he can grow anyway. Then they start to walk to the Kumite arena. When they get to the entrance to the corridor, he still has his facial hair when the guy says "OK USA!" But, when they actually enter the arena for the Kumite, he's completely shaven.
Audio problem: When the Kumite's history is being announced by the black dragon leader, just before the first fight, every word he says has been dubbed. Hardly any of his mouth movements match his words.
Other mistake: During the second day of fighting, fights are shot out of order. For example, When Chong Li and Suan Paredes fight, the (fighters) benches are nearly empty (the one on the right is empty aside from Chong Li's assistant), but in several fights following, they are more than half full. In fact, Paredes can be seen sitting on his bench in shots after Chong Li snaps his leg in half.
Continuity mistake: In the final fight scene Jean jumps over Chong after being blinded. He does a midair flip to the back of Chong. In the next shot Chong is completely turned around despite having about half a second.
Factual error: In Chong Li's second fight where he splits the other fighter's shin open the South Korean flag on his manager's black sweatshirt is upside down.
Factual error: Chong Li's South Korean emblem on his headband is upside down before breaking the ice blocks. And you can see his trainer has the emblem on sideways on his arm.
Suggested correction: Someone wearing a headband, that they can't even see since its on their head, upside down doesn't qualify as a mistake and happens all the time.
While it's possible to happen, generally speaking, upside down flags or flag symbols are considered valid mistakes. Just like the patch wouldn't be sewn on sideways.
Continuity mistake: When Tanaka gives Frank the katana, Frank moves it to one side of his head, then the other. Tanaka then puts his hand on Frank's shoulder. The arc of the katana blade is pointing away from Frank and towards Tanaka. The camera then cuts to a shot behind Frank. Now the arc of the blade is pointing towards Frank. (00:16:30)
Revealing mistake: During the fight montage, the winner of the first match wins by kicking his opponent in the face. His foot never makes contact.
Continuity mistake: Before Frank does the dim-mak, the top brick in the middle is a lighter color with 3 darker red bricks below, followed by the last brick. After the break, the top 2 bricks are now a lighter color with 2 darker red bricks below.
Other mistake: When Ray and Frank are playing "Karate Champ", they're suppose to be playing against each other. But the screen shows the game is set for 1-player mode, otherwise it would have both "1 up" and "2 up."
Factual error: The time period of the story has been updated from when Frank Dux claims he actually participated in the Kumite, however the scenes with young Frank take place in the mid to late 1970's. When Tanaka's son is assaulted, the clothing and hair styles worn by young Frank and his schoolmates is not period accurate and is contemporary to when the movie was filmed. One child is even wearing a Bartles and Jaymes T-shirt, a product that didn't exist until 1981.