Abstract: The technology of “dual threshold point expansion and successive decrease circulation processing” is introduced into the computer image automatic processing system for fragmentation distribution of blasting lumps and rocks to make the image's binary processing.Based on the techniques of binary，twice denoising smooth of blasting lumps images are made，and the Laplace operator edge detection is used to determine the rock boundary.Cooperating with the regional growth method of monotonous links，the least distance segmentation method into regional segmentation is creatively proposed.The double logistic regression analysis on the processing results is carried out by using R-R function，acquiring the distribution results of blasting lumps and rocks.Test results show that the system has a high precision of measurement with the error of usually no more than 10%，which can meet the requirements of practical application，Also，This test method has a very good development prospect.

Key words: Image analysis, Fragmentation distribution, Blasting, Blasting lumps, Rock