Abstract: Aiming at the anchoring failure of heterogeneous rock strata, based on bolt bilinear strengthening constitutive model and considering the deterioration of tension and compression stiffness of bonded layer, a three-dimensional refined numerical calculation model of heterogeneous rock strata, bonded layer and bolt anchoring system was constructed. The stress transfer law of anchor bolt and deformation and failure characteristics of anchor system under granite-granite(H-H), granite-sandstone(H-S), sandstone-granite(S-H) and sandstone-sandstone(S-S) rock combinations were analyzed, and the influence law of different lithologic combinations on shear mechanical properties of anchor composite rock strata was revealed. The results show that the shear resistance is mainly in the local area of the bedding surface under compression shear state, and the maximum shear stress exists near the bedding surface. The peak value of bolt normal stress is related to the sequence of bolt penetration. Under the same boundary condition, the effect of rock bolt limiting shear movement of homogeneous hard rock is the best. The anchorage system near the bedding surface is prone to de-bonding failure and the position with large reduction rate of the stiffness of the bonded layer is always located in the soft rock part.