In this paper, it takes the long jump sports injuries, for example, and obtains that the most relevant factor with long jump athlete’s sports injuries is the technical action error by using principal component analysis and Pearson correlation analysis, uses the bio-mechanics and dynamics techniques to conduct research and analysis for the long jump run-up, jump preparation, jump, vacated, and landing five action essentials, obtains that the take-off angle increases with the decrease of the jump speed and the distance of the long jump increases with the increases of the take-off speed, thus obtains that the best take-off angle and speed not only improve athletic performance of the long jump athletes, but also provide a professional and scientific prevention method for the long jump sports injury.