Abstract: Thin-walled beams with constant sections, whose geometrical centers and shear ones do not coincide, are mainly concerned. Based on the theory of Timoshenko beams and thin-walled members, rotation displacements and warp angles of sections are independently interpolated in order that traverse shear deformation and warp engendered by transverse shear and second-order shear stress be included. Through the equation of virtual work, element stiffness matrix is deduced. Some examples given in the context verify the accuracy of the suggested model and its availability in the engineering and confirm the indispensability of considering the influence of coupled bend and torsion when there is at least one asymmetric axis in the sections.