Abstract: Based on the particle flow code (PFC), a geometric model for simulating the failure mechanism of the rock specimen with staggered joints was developed in the study, and the macro mechanical parameters of the specimens were calibrated. On the basis of the servo module, the variation in the direct shear strength of the specimens under the conditions of different normal stresses was simulated. The monitoring module for the crack propagation was prepared by fish language inserted in the PFC. The crack propagation law and the failure mode of the specimens with staggered joints were described during the direct shearing process from microscopic point of view, in addition, a quantitative analysis of the failure law of the specimens was carried out by tracking the numbers of the microcracks. The model testing results show that the shear stress-shear displacement curves are mainly divided into four stages, and along with the increase of the normal stress and the shear angle, the shear strength increases linearly. The cracks of the specimens mainly occur at the joints, which appear as break of intermediate blocks and upper and lower joint protrusions. And the shear angle has an important influence on the failure scale of the specimens. Compared with the single joint specimens, the shear strength and the failure scale of the specimens having the staggered joints decrease greatly but the failure law is different. The difference of the joint friction property has been further considered. From the model tests it is found that the stronger the friction in the joints, the greater the shear strength and the failure scale of the specimens. The simulation testing results given by this paper can provide a reference for the study of mechanical properties of the rock mass having complex joints.