Weak rock tunnel in the engineering practice and experiment research have shown strong, easy to cause the rheological properties of rock deformation caused by excessive instability. The authors established anti-analysis system based on viscoelastic finite element method theory by monitoring the weak surrounding rock excavation process of Yunling left cave entrance according to the New Austria Tunneling Method and analyzing the initial value of surrounding rock displacement convergence and secondary support and lining of the pressure changes. By using ANSYS finite element program, the excavation process was simulated, and the actual field measured values were compared with the calculated data. The study provides a scientific basis and technical guidance for support design and construction of tunnel with safety and reliability.