According to the image characteristics of laser active imaging,an improved Canny edge detection algorithm was proposed.Based on Canny edge detection,the algorithm used the voting median filtering and lifting wavelet transform to replace the traditional Gaussian filter,and calculated the grades of filtered images by using an adaptive method of 3×3 adjacent regions gradient.Simulation results show that:the algorithm can improve the anti-interference capability and robustness of traditional Canny operator,keep well the detail edge information and has fine real-time performance,which makes it more practical.