Blasting is the main excavation method of rock slope at present.In order to evaluate the effect of blasting damage on the stability of engineering slope,the weakening law of blasting damage is discussed based on the disturbance factor D in Hoek Brown strength criterion.Using the spatial variation of D characterized by change of longitudinal wave velocity in rock mass,the exponential type of D was obtained to reflect the spatial distribution of blasting damage degree.The impact on the factor of safety of the distribution rules as well as the influence area of the disturbance factor D were explored consequently.For the case in hand,the computed factor of safety is 1.14 when the value of D is gradually changed according to the law of exponential distribution,and the factor of safety increases to 1.39 and 1.47 respectively when it is gradually changed according to the law of linear and quadratic distribution.Considering the gradual change of exponential distributed D value in the blasting damage zone,the systematic bolts can effectively compensate the loss of the slope stability due to the rock mass mechanical properties weakened by blasting.The results show that considering gradual weakening of D can better reflect the actual effect of blasting damage on slope stability,the blasting damage can be effectively controlled by the system bolt,and the different distribution patterns and ranges of D have great influence on the factor of safety.