Abstract: A model of orthotropic stiffened laminated composite conical shells is established. The vibrational characteristics of stator end winding and its fastener of a large turbo-generator are studied. With the virtual work principle, the basic kinetic equations of the stiffened laminated composite conical shells are established and expressed in terms of the displacements of stator end winding. Formulae of elastic constants of a single winding and the whole structure are given. With Galerkin integration method, the generalized eigenvalue equations for natural frequencies of end winding are derived. The natural frequencies of steam ends and exiting windings of the turbo-generator are obtained through numerical calculation, and the numerical results are testified with experimental data.