Abstract: Based on Timoshenko beam theory, as well as FEM and laboratory testing, the effect of shear deformation on box girder element is analyzed. According to the theory of elastic thin plate, equivalence principle and computational accuracy of three different analogical methods are analyzed under several boundary conditions. The shear modulus and practical deflection modification method of the equivalent solid floor are proposed. The results show that the shear deformation effect of the hollow floor is much larger than the solid floor. The analogue method proposed by the Code is better than other analogical methods in the aspects of section force and moment. However, all the existing analogue methods based on the equivalent flexural rigidity cannot calculate the shear deformation exactly. The proposed shear modulus and practical deflection modification method based on “equivalent shear rigidity” are suitable for both structurally isotropic hollow floor and structurally orthotropic hollow floor, and can predict the deflection more precisely. The conclusions can be used as reference for structural analysis and design.