Abstract: Aimed at the stability analysis of layered rock slope affected by the erosion, impulse, and compaction of the weak intercalation caused by blasting, and applied on the theory that blasting gas is isoentropy adiabatic expansion in the lamination cracks and charge hole, the quasi-static mechanical model for the lamination of weak intercalation in layered rock slope was established during the deep-hole blasting. The explicit expressions of the quasi-static pressure in the blasting cavum and the critical lamination length of the weak intercalation were deduced. Through the study on the raise effect of the rock mass caused by the blasting gas wedging into the weak intercalation, the quantitative relationship between the stability factor of the latency slip and the parameters of charge, the mechanics parameters of the rock and the geometry size of the slope was obtained. The blasting dynamic stability of the two typical layered rock slopes was analyzed by using the quasi-static mechanical model presented in this paper. Analyzed results are in agreement with the engineering practice.