Abstract: In order to adapt to the complex external environment, there may be sudden changes in the longitudinal structural stiffness of shield tunnels. Based on previous studies, a Timoshenko short beam-spring shield tunnel model considering the longitudinal variation in the structural stiffness is proposed. The continuity of the foundation soil behavior and the arbitrary boundary conditions are considered through the Pasternak foundation model and the boundary springs, respectively. The coupling solution of the longitudinal deformation of the shield tunnel induced by external loads is derived by the finite difference theory. The correctness and effectiveness of the calculation method are verified with the model degradation, the numerical model, and an actual engineering case, and the influence of high-stiffness segments on the longitudinal deformation of the shield tunnel is investigated through a parameter analysis. The results imply that the use of high-stiffness segments can effectively restrain the tunnel settlement and the deformation of circumferential joints within the high-stiffness segment section, but the stiffness difference will cause sudden increases in the joint deformation at both ends of the high-stiffness section. The larger the stiffness difference between the high-stiffness segment and the regular segment, the smaller the tunnel deformations within the high-stiffness section, but the more apparent sudden increases of the joint deformations at the ends of the high-stiffness section can be observed. There are significant differences in the deformation control effectiveness under various combinations of the high-stiffness section length and the structural stiffness ratio, and unreasonable parameter combinations may even aggravate the tunnel deformation.