This article presents an automatic counting method using digital image processing to solve difficulties in manual Solar Energy Wafer(SEW) counting in industry production. By analyzing the image texture of overlaid wafers, the author firstly locates wafer area employing first-order statistics method and edge detection projection, and then performs counting by extremum analysis in this practical application. The experiment results show that the algorithm is highly accurate with the locating accuracy up to 94% and the counting accuracy up to 95%, and it is convenient and applicable.