This paper presents a simple stress resultant 4-node shell element for geometrical non-linear analysis. In order to model smooth surfaces and/or stiffened structures, a simple and efficient technique for finite rotation is adopted. By means of suppressing the component of singular rotation effectivley, convenient use of six degrees of freedom is possible without deteriorating the robustness and the convergence rate of the classical 5-dof formulation. In the formulation of shell element, section eccentricity is also considered to model stiffened structures. Through numerical experiments the effectiveness of the proposed method is demonstrated.