Structures consisting of frames can be considered as shear structures under certain assumptions. The frame can be idealized as an equivalent shear beam in this case. In this study, the dynamic characteristics of non-uniform frames were investigated. For this purpose, the method of differential transform was used to solve the governing differential equation of the equivalent shear beam. This shear beam represented the structure of which shear stiffness varies along the height. In this study, the contribution of the axial deformation was taken into account with the help of equivalent shear stiffness. The least squares method was used in order to determine the parameter that defines the change of the shear stiffness. Thus, the dynamic characteristics were determined more realistically. Tables were prepared for use for the determination of the dynamic characteristics of frame structures with non-uniform shear stiffness. Response spectrum analysis can be easily conducted using these tables. The suitability of the approach was investigated through examples at the end part of the study. The suggested method could be used safely during the preliminary design stage. It is particularly easy to understand the structural behavior due to the usage of fewer parameters.