Based on the assume that the strength of micro-element of surrounding rock accords with double-parameter Weibull distribution,the failure probability and critical failure probability of micro-element of surrounding rock were analyzed.According to different integrity of surrounding rock its damage after roadway excavation was analyzed.The numerical simulation of excavation damage of roadway surrounding rock with different homogeneity was carried out by using a rock failure process analysis code(RFPA).The results indicated that with the increasing of the homogeneity(i.e.integrity) of surrounding rock the initial damage postponed,the critical failure probability was becoming lower.When the load of micro-element did not reach the statistical average compressive strength,lower the homogeneity was,larger the damage was.After the load of micro-element reached the statistical average compressive strength,higher the homogeneity was,larger the damage was,so surrounding rock with high homogeneity has high hazard rate,and the hazard often burst up.After excavation the damaging degree of roadway surrounding rock is closely related to its heterogeneity and compressive strength.The results of damage analysis of surrounding rock based on Weibull distribution agree with that of simulation analysis.