To research the geometric nonlinear problem of tapered beam with shear deformation, based on Timoshenko theory, the displacement and rotation independent interpolation method was adopted to obtain the shape functions of tapered beam considering shear deformation, whose inertia moment varied quadratic. Then, started from the virtual work increment equation, the geometric nonlinear incremental equilibrium equation of the plane tapered beam element was established, including axial force, shear effect, bending effect and its coupling term, and the large displacement tangential stiffness matrix of the tapered beam was obtained. Finally, the classical examples are calculated, and the results show that the proposed method is accurate and effective.