Abstract: Two longitudinal displacement difference functions are employed to accurately describe the variation of shear lag in thin-walled curved I-beams with different widths of wing slabs ( ). Thus, a new approach is proposed to analyze the mechanical characteristics of curved I-beams, considering the effect of flexure , warping torsion , shear deformation and shear lag effects. The minimum potential principle is applied to establish the governing differential equations and corresponding natural boundary conditions. And closed-form solutions of generalized displacements are obtained. A comparison was made among the finite shell element solutions, the traditional method solutions and analytical solutions proposed by this paper, and the validity of the proposed approach is verified.