The present application provides a method for automatically detecting a wafer backside brightfield image anomaly, at least comprising: processing wafer backside brightfield images by means of histogram equalization, so as to obtain processed images; compiling statistics for a gray histogram of the processed images; calculating the number of abnormal pixels in each of the images; and providing a threshold, and highlighting the image with a score less than the threshold. In the present application, the wafer backside brightfield images are analyzed by means of image preprocessing and a specific calculation method, so as to quickly and automatically detect an abnormal wafer backside image.