Abstract: With the quick development of computer image detection technique, image boundary inspect method has become the field of image processing and computer vision research focus, digital image boundary inspection is image segmentation, image recognition, image analysis for instance area shape extracting the important foundation. Based on Canny operator manually select the threshold improperly, which result in edge detection has some ineffective shortcomings. In this study, the method is presented an reinforced Canny boundary inspection to automatically produc an adaptive threshold for Canny edge detection operator. In the algorithm, it can create the threshold parameter automatically, by the mean square error and average gray of the image. Therefore this method can avoid errors caused by manual input and obtain a desired edge effect.