The scene in which Kurt has meat tied to his leg and is chased by Xian Chow's dog was inspired by a real-life event in which a young Jean-Claude Van Damme was ordered by his karate teacher to wear a protective suit and withstand the attempts of a trained dog to pull him to the ground.
Michel Qissi was a technical advisor/choreographer when he overheard the production crew say they were looking for a tall oriental-looking guy with a background in Muay Thai. He volunteered, and got the part of Tong Po.
Tong Po is mistakenly billed as playing himself (on the film's credits). In fact Michel Qissi played the villainous Thai for this film and its sequel Kickboxer 2: The Road Back (1991). Kamel Krifa played the character in the 4th. Qissi can also be seen in two other Van Damme movies, Bloodsport (1988) and Lionheart (1990). In Bloodsport Qissi is the fighter that gets his leg broken by Chong Li. In Lionheart (AWOL) Qissi plays Moustafe who alongside another legionnaire is trying to bring Lyon from America back to Africa.
The title held by Dennis Alexio's character in the movie - the International Sport Karate Association (ISKA) Heavyweight Championship - is a real championship and has been held by Alexio during his fighting career. The belt in the movie, however, is not modeled after the actual belt.
The camp which Jean-Claude Van Damme's character visits during his search to find a trainer is the Sor Thanikul gym of Bangkok. Though defunct since 2003, it was a genuine training center for Muay Thai practitioners - housing over 50 kickboxers at any given time.
The movie is set in Thailand, but apart from key exterior locations such as the Temples, Bangkok streets and night life, the Thai Boxing school and stadium, the majority of the movie was shot in Hong Kong, with Master Xian's house being built in Sai Kung, at Shing Fung studios.