Factual errors: Yoshida's hakama is worn backwards.
Revealing mistakes: During the extreme close-up of Chen's eyes in the final fight with Petrov, his contact lenses are visible.
Anachronisms: Outside the park that only grants admission to non-Chinese, a couple in 1970s clothing and haircuts walk by. Also, deep in the background 1960s cars are parked.
Revealing mistakes: In the opening, at the funeral of the master, there is a rain storm but the dirt they are shoveling into the grave is dry.
Revealing mistakes: At the beginning of the second nunchaku fight, the nunchaku bend, revealing that it is soft rubber and not wood or metal.
Crew or equipment visible: In the final battle as Suzuki is kicked through the shoji screen, you can see his white belt wrapping itself around the stunt wire used to lower him down to the ground below.
Anachronisms: In the first fight against Yoshida at the HonKyu Dojo, as Chen stands waiting, a picture of Gichin Funakoshi, "The Father of Modern Karate", is in the background. The movie takes place in 1909, but Funakoshi didn't introduce Karate from Okinawa to Japan until 1932. Also, the Japanese students are clearly practicing and dressing like Judo students, not Karate.
Miscellaneous: When Bruce is spinning the two Bushido students in the Bushido school, they are clearly two lightweight dummies.
Continuity: The "Magic Pants" goof. Bruce Lee enters the Japanese Karate school for the first time carrying the framed and glass-covered "Dung Ya Bing Fu" sign. A fight between Bruce and the entire dojo breaks out. As he whirls around fighting his waist sash loosens and his kung fu pants sag deeply, revealing about three inches of white underwear from the back. Then a sudden cut shows Bruce posing motionless having defeated the current round of Japanese attackers. His pants? Tied up around the waist, nice and snug. Now that's some kung fu!