To study the overall completion time of taekwondo side kick, the angle change of hip joint, knee joint and ankle joint, the relationship between the three axial changes of athletes’ body center of gravity and the quality of action completion. Three groups of 12 subjects of different levels were selected to capture the biomechanical characteristics of the subjects’ different stages of action using high-definition infrared camera and force measuring table. Results: The completion time of side kick was shorter, the range of joint change was closer to the theoretical value, and the test results of professional group were in the middle. As a result, the displacement of the body center of gravity in the athletes’ group is small and stable, so it can obtain faster instantaneous speed and strike strength. Conclusion: Taekwondo athletes should maintain the stability of body center of gravity and the rationality of joint angle in order to better complete the action quality, shorten the action time and improve the kick intensity; the results were verified numerically by multiple regression linear analysis model, and the results showed P<0.05.
