The internal force redistribution would occurs to main tunnel lining due to structural system variation during the cutting process of the cross passage constructed by mechanical method. Hence, in order to analyze the variation laws of internal force redistribution of tunnel lining and summarize its force transmission mechanism, the structural mechanism of main tunnel lining during construction process of cross passage of Wuxi Metro constructed by pipe jacking method is studied. The analytical results show that: (1) The deformation of each ring during construction is small, which indicates the safety of the method adopted. (2) The effect of the redistribution condition of the internal force is obvious. (3) Under the cooperative action of auxiliary facilities such as internal support, the internal force redistribution in the ring mainly occurs in the cutting ring, and the internal force transmission between the rings mainly occurs in the halfcutting ring during the demolition stage.