Fluid-solid coupling behavior of reservoir rock is the basis of stratum back washing, ABAQUS-6.5 software is used to conduct three-dimensional elastic-plastic concretion numerical simulation for back washing stratum well washing deformation, combined with the technology of water, the deformation process of the reservoir rock is regarded as a coupling process, it’s elastic plastic fluid solid coupling. Use Mohr-Coulonb as the yield condition of rock mass to simulate 16 holes per meter of perforating, at the same time, the influence of different crustal stress status, permeability and rock mass mechanical property on oil well sand production was studied. The calculation results show that, when the elasticity modulus of stratum is larger, the rock stratum permeability will be higher, the stratum horizontal crustal stress will be less, the stratum is more difficult to sand product wash pressure can be improved appropriately.