Abstract: Fault is an important channel for the migration and diffusion of groundwater flow and pollutants. However, there are few researches on the simulation of groundwater pollution migration of landfill by fault at home and abroad. [Objective]The purpose of this paper is to build a groundwater flow and solute transport model including fault permeability，[Methods] based on GMS software to simulate and predict the impact of characteristic pollutant seepage on groundwater environment and water delivery tunnel under different working conditions. [Conclusion]The simulation results show that under normal working conditions, due to the anti-seepage measures at the bottom of the plant, the diffusion range of pollutants is basically limited to the inside of the plant, and the maximum concentration of pollutants in the center is less than 0.5 mg/L. Under abnormal conditions, the pollutants in the leakage scenario of pollution source No. 1, No. 2 and No. 3 diffuse to the location of the water delivery tunnel on the 800th, 4015th and 1095 days, respectively. The vertical diffusion range of pollutants in the three simulated scenarios gradually increases, but there is little difference in the plane diffusion range. On this basis, i the simulation of groundwater pollution caused by the enhancement of the permeability of the fault zone is carried out. The results show that the enhancement of the permeability of F4 fault has a great environmental risk to the pollutant migration under the pollution source scenario No. 1 and No. 3. Under the No. 2 pollution source scenario, the enhanced permeability of F3 fault does not bring greater environmental risk to the tunnel area. The research in this paper can provide scientific support for groundwater pollution prevention and risk assessment in the study area.