The classic defects recognition algorithm is studied with an aim at printing defects detection ,and this paper puts forward a recognition algorithm that processes edge and non edge points separately in print defects detection.The algorithm is based on statistical process principle according to the characteristic difference of pixel edge points and non edge points; the statistical threshold method is used for non edge points, and the combination of field average value and gradient value is used for, edge points.The algorithm was proved by experiment and it can effectively eliminate the false defects in the process of extracting the real defects.