Abstract: This article aims at the influence of fault structure on permeability-improved effect and coal-bed deep-hole cumulative blasting safety. The dependence of crack generation and growth upon fault was analyzed on the base of theoretical analysis, numerical simulation and field test. The effect of fault on blasting safety was discussed from two aspects of gas occurrence and blasting energy propagation. Numerical simulation results demonstrate that fault affects blasting crack growth and stress wave propagation. Field test shows that permeability-improved effect in the fault-affected zone is 1.6 times better than that in no fault-affected zone, and that the fault zone, which easily causes punching phenomena, has important influence on blasting safety.