Abstract: In order to study the influence of joints to the mechanical characteristics of rock mass and the evolution of instability damage, by using anchoring through joint rock PFC^2D doing indoor shear test and numerical simulation method, studying the anchoring through joint rock mass under different joint angle shear performance of the mechanism of behaviour and failure mode, the result shows that:(1)with joint angle changing, it presents different failure modes through joint rock samples, and anchor through joint shear strength of rock mass and the shear displacement curve is not a linear growth, but a trend of "double hump".(2)During the shear test of the anchorage system, the contact azimuth angle of jointed surface particles changes in a certain extent, mainly in the vicinity of the anchor rod and the joint inclination angle.(3)During the shear test the anchorage system, it will generate cracks in the anchorage system due to the fracture of the interparticle bonding bond. The fewer the number of cracks are, the higher the shear strength is. The cracks include tensile crack and shear crack, and the number of tensile crack is much larger than the shear crack's.The results can be used to predict the actual failure mode and evaluate the stability of rock mass engineering.