Based on three-dimensional cellular automata (CA), a new stochastic simulation model to simulate the microstructures and particle flow of talus deposit is proposed. In addition, an auto-modeling program CARS is developed, with which numerical simulations can be conducted conveniently. For the problem of simulating mechanical behaviors of talus deposit, spatial arrangement or sphere shapes should be considered. In the new modeling method, four sphere arrangement models are developed for the particle flow simulation of talus deposit. Numerical results show that the talus deposit has the mechanical characteristics of typical stress-strain curves, as other rock-like materials. The cohesion of talus deposit decreases with increasing rock content, while the internal friction angle increases with increasing rock contents. Finally, numerical simulation is verified with the results of field test. Based on three-dimensional cellular automata (CA), a new stochastic simulation model to simulate the microstructures and particle flow of talus deposits is proposed. For the problem of simulating mechanical behaviors of talus deposit, spatial arrangement or sphere shapes should be considered. In the new modeling method, four sphere arrangement models are developed for the particle flow simulation of talus deposit. mechanical properties of typical stress-strain curves, as other rock-like materials. The cohesion of talus deposit decreases with increasing rock content, while the internal friction angle increases with increasing rock contents. Finally, numerical simulation is verified with the results of field test .