In order to find out the horizontal axis offset law of the tube sheet caused by small curvature radius shield tunnel construction, and to prevent the occurrence of undesirable phenomena such as tube sheet misplaced breakage. Based on the modified longitudinal equivalent continuity model, the ellipticized deformation of tunnel convergence and the influence of comprehensive factors of curved tunnels are considered. By constructing the deflection differential equation of the Winkel foundation beam under the condition of small curvature radius, the prediction model of horizontal axis offset of the tube sheet in the construction stage of small curvature radius shield is established. The engineering applicability of the prediction model is verified by relying on the shield tunnel project of Nanchang City Railway Line 3. The results show that: when the tube sheet is assembled within 6 rings, the maximum error between the theoretical value of the prediction model and the monitoring and simulation values is 13.36% and 25.68%, respectively. The maximum errors between the theoretical values and the monitored and simulated values are 4.91% and 8.95%, respectively, when the pipe pieces are assembled in the range of 7 to 22 rings. The theoretical, simulated and monitored values of the tube sheet assembled in the 30th ring are -20.562 mm, -22.370 mm and -20.949 mm respectively, and the error between the theoretical and monitored values is less than 5%, and the overall trend is basically the same, which can effectively solve the problem of calculating the horizontal axial deviation of the tube sheet in the construction of shield tunnel under the condition of small radius of curvature.