Abstract: In order to measure the morphological parameters of cracks for rock and soil accurately and quickly,with the application of computer image processing technology,a set of recognition and quantitative analytic methods of crack images were introduced.Nodes and skeleton of crack network were traced out by the operations of binarization,crack restoration,noise reduction and intelligent recognition.Morphological parameters of cracks,such as length,width and direction,were computed by further recognition methods.Furthermore,a new method was proposed to evaluate the connectivity of crack network.A software,Cracks Image Analysis System(CIAS),developed based on these technologies,was applied to the recognition and morphological quantitative analysis of soil crack images.The proposed method offered a reliable basis for the quantitative analysis and recognition of cracks,and thus the morphological parameters could be obtained more scientifically and efficiently.