Wah Yuen doubled for Bruce Lee in the fight scene between Chen and Yoshida where Chen does a somersault, while Jackie Chan doubled for the villain Suzuki when he is kicked back through the large paper windows.
The international title of this film was "Fist of Fury". In the United States the English dubbed version was released under the title "The Chinese Connection" to avoid confusion with "Fists of Fury", the title for the U.S. release of Bruce Lee's previous film The Big Boss (1971). The U.S. title was a play on the title of the highly popular film The French Connection (1971).
In the film, Bruce Lee's character sets out to avenge the death of his teacher Huo Yuanjia and at one point during the film, the Chinese Wushu students are called "sick men of Asia" by their rivals. In real life, Huo Yuanjia was a legendary Wushu martial artist and in 1901, accepted the challenge of a Russian fighter who called all Chinese people "sick men of Asia".
While filming in a park, Wei Lo had to contend with local street gangs, whose leaders would demand payment for using 'their bit' of the road. The protection money was usually paid, much to the annoyance of Bruce Lee, who had to be physically restrained from attacking them.
Jackie Chan doubled for Riki Hashimoto for the scene where Chen kicks him out the window. He took the kick and flew several feet. Bruce Lee immediately checked to see if he was okay. Chan would later play a guard Lee kills in Enter the Dragon (1973).
Contrary to rumors Steve Martin does not play the white-haired policeman who shoots Lee at the end of the film. Hong Kong movie expert Bey Logan originated the rumor with a tongue-in-cheek remark in his commentary for the DVD issued by Hong Kong Legends (HKL). Logan apologized and retracted the remark in a later commentary recorded for HKL's reissue of the DVD.