Abstract: A novel composite element frequency selective surface is proposed, and the integral equation of unknown electric field of the periodic surface is derived by using modal matching method. The electric field basis function of the novel composite element is proposed. Then solving the integral equation by moment method, the curves of frequency response characteristics under the various incidences can be obtained. The results show that, the novel composite element frequency selective surface has stable dual-band under the various incidents, which will be very popular applications in communication system and radar system in the future.