Abstract:A test system of a rectangular cavity with a Parallel Plate Resonator(PPR) inside, working between 3 GHz and 6 GHz, is designed and analyzed. Its geometric structure is discussed in detail and its sizes can be determined by three sets of modes and frequencies. In the context of the resonance of the cavity, the mode of the PPR can be identified, the values of Q are obtained as well, and therefore, the microwave surface resistance(Rs) can be determined. The electromagnetic characteristics of high-Tc superconductive film can be obtained by analyzing the simulation results. The high-Tc superconductive material can be applied to microwave devices in RF and some higher bands.