Abstract: In order to study the aseismic performance of a steel structure with wall panels, a full scale model with stiffened steel wall panels was tested under low-frequency cyclic loads. Based on the recording of experimental phenomena and processed data, the failure mode and energy dissipation mechanism of the structure were analyzed with regard to the loading capacity, ductility, stiffness and energy dissipation capacity. The results showed that the specimen exhibited excellent ductility and energy dissipation capacity. The hysteretic loops present a ‘spindle’ curve. The stiffeners improved the work condition of the steel panels and increased the stiffness and loading capacity of the panels. The failure mode of the structure was induced by local buckling and the crack of the column and local buckling of the infill panels,and plastic hinges were formed at the bottom column-beam connection. The experiment results provide a basis for further studies and engineering application of this structure system.