Abstract: From constant to variable, the moment amplification factors of cantilevers with different cross-sections were studied in this paper, while both shear and flexural deformations were considered simultaneously. A moment amplification factor formula for the cantilever with a constant cross-section was obtained by solving differential equations. By taking further research on cantilevers with linearly changing axial forces, the bending stiffness and shear stiffness, the variation of the moment amplification factors along the height of the cantilever can be described by the proposed approximate formula. The factors were also calculated by the finite element method, and the comparison shows that the accuracy of the given formula is suitable.