Abstract: Most of the existing image matching methods based on the invariant moment of image histogram can not adapt to the images with large rotation.A concept of invariant moment of slope angle histogram(IMSAH) is introduced and applied in image matching.Edges of images are fitted by groups of lines,and the consistency of the slope angles is used for matching.Experiments show that IMSAH can be used as an image descriptor,and the image matching based on IMSAH is feasible.