As a powerful component of a circuit breaker, the reliability of energy storage spring plays an important role in the drive and control the operation of a circuit breaker motion process. A non-contact testing method of spring deformation characteristics based on image matching tracking technology is proposed: the high-speed camera is utilized to capture the image sequence of energy storage spring extension-contraction process, and the first coil of the movable end of the spring is taken as the matching target. Then, the sequential similarity detection-pyramid (SSD-P) matching algorithm is utilized to search the target frame by frame to obtain the target coordinates of the key frame and parameters of spring deformation characteristic. A sequence similarity detection image pyramid matching based on recognition region estimation (SSD-P-E) algorithm is proposed. The subsequent frame target position is predicted according to the front and rear frame position correlation, the recognition area is dynamically adjusted according to the prediction to eliminate the interference of similar structures on the matching results and improve the matching speed and accuracy. Finally, the experimental results show that the method can effectively detect the extensioncontraction deformation characteristics of the circuit breaker spring release energy process when the circuit breaker is working. INDEX TERMS Circuit breaker, spring deformation characteristics, sequential similarity detection, image pyramid matching, identification area estimation.