Abstract: The key techniques of SHI Zhiyong's 2-time surpassing world records of the clean and jerk were analyzed to provide scientific and technological support for the preparation of Tokyo Olympic Games.Two highspeed cameras were used in the competition scene to shoot the fixed-focus of the competitions. A SIMI° Motion7.50 three-dimensional motion analysis system was used to analyze SHI Zhiyong's clean and jerk movements video.In the clean stage, the knee flexion amplitude was larger, and the peak angular velocity of hip and knee extension was faster when SHI ZhiyongY lifted 199 kg. These may be beneficial for promoting the power effect of the second pulling. However, the maximum falling velocity of the barbell may be a potential problem of the catch stability.In the jerk stage, the peak angular velocity of hip and knee extension was further improved, and the peak velocity of barbell increased when SHI Zhiyong lifted 199 kg.In addition, a possibility of further performance improvement may be predicted by the peak height of the barbell. As for the stability parameters, the Y-axis offset of barbell center of gravity was controlled perfectly in the two lifts. However, the distance between the barbell center of gravity and the body center of gravity was too large at the end of the two pulling periods, which may be related to the technique of lifting elbow and turning wrist.Enhancement of the explosive power and coordination of the hip and knee extensor muscles could be a key technique assisting SHI Zhiyong to surpass the world record again.