Abstract: The fibrous material image captured from Scanning Electronic Microscopy(SEM) has low SNR,and the objects in image overlap together.Region segmentation using concave spot extraction was firstly performed in this paper.But the results show that this method has shortages in precision,especially for complex overlapping segmentation.To solve this problem,the method based on watershed transform was further proposed in this paper.Distance transform was used for preprocessing the image to get gray level distribution.The watershed line was achieved to mark the boundaries of different objects.Experimental results show that the segmentation approach performs more successfully.