The invention discloses a test method for a motion characteristic of a high-voltage breaker based on an improved Gaussian mixture model. The test method comprises the following steps that a pixel gray scale histogram of a gray image sequence of the breaker in the operation process is solved, and median filtering is used to eliminate isolated noise spots; the Gaussian mixture model is established for pixel points, and a foreground point mark matrix is generated; parameters are updated, a counter matrix is established, and Gaussian distribution matching of the changing pixel points is processed correspondingly; background weights and coefficients are added when background distribution is determined, foreground and background in the image are distinguished, and the foreground point mark matrix is updated; and the foreground point mark matrix of a frame of image is subtracted from that of an adjacent frame of image to solve a centroid of a motion mechanism, the motion speed is determined according to difference between positional coordinates of the centroids, and the motion characteristic is obtained. According to the invention, the improved Gaussian mixture model including the background weights and coefficients, the foreground point mark matrix and the counter matrix is provided, and applied to test the motion characteristic of the breaker operation mechanism, test operation of non-contact high-voltage equipment is realized, and the adaptability is higher.