Abstract: The stability of the slope excavation face of a shield tunnel is studied with the upper limit analysis meth? od based on the existence of a slope on the overlying soil layer of the tunnel, to build a stability analysis model of slope excavation face and provide a calculation formula of ultimate support pressure. Through the comparison of numerical simulation results, the impact of various factors (thickness of covering soil, cohesion and angle of internal friction) at a constant slope is analyzed; the diagrams and tables are used to provide the variations in the influencing coefficients of support pressure at three different slopes of covering soil with the burial depth. The results show that the support pressure is reduced with an increase in the soil cohesion and angle of internal friction and is increased with an increase in the burial depth, and the support pressure is in direct proportion with the slope of covering soil.