In view of the shortages of the present motion information collection of the elbow joint control muscle group, a new method of motion information collection of the elbow joint control muscle group based on PVDF sensor was proposed in this paper. The sensing principle of PVDF film was described and the best structure of the sensor's cantilever was obtained through the design and test. Besides the sensor array and signal conditioning circuit were designed. The content of the actual test was measured with the dumbbell arm flexion and extension of barehanded and 10 kg loaded, and the results show that the method is economical, reliable and practical, and has the ability to collect and monitor the motion information of the elbow joint control muscle group during exercise effectively.