Abstract: For low accuracy and poor adaptability existed in current detection methods of joint twitching of steel cord conveyor belt, a detection method of joint twitching of steel cord conveyor belt based on X-ray image was proposed. Firstly, X-ray image is enhanced by use of image enhancement method based on Retinex theory. Then joint edge is detected by Sobel edge detection operator so as to extract centroid of the joint edge as joint point, and the joint points divided into different levels are fitted linearly. Finally, joints of current image and reference image are matched according to number of steel wire rope between adjacent joints, and distances from the matching joints to the corresponding fitting lines are compared. Joint twitching is detected according to whether the distance difference is larger than a certain threshold value. The test results show that the method can detect joint twitching accurately with high joint recognition rate.