A new microwave band-stop filter based on two-dimensional photonic crystal is proposed in order to improve the transmission quality of the wireless communication system. The filter consists of a line defect waveguide and Aubry-Andr-Harper(AAH) resonator. By changing the distance between the AAH resonator and the main waveguide, the coupling coefficient between them is increased, and the filtering of the microwave band at 1 668.3 μm is achieved. Based on the Finite Difference Time-Domain(FDTD) principle, simulation is performed in Lumerical platform. The results show that the filter has excellent performance: the center wavelength of the stop band is 1 668.3 μm, the stop band attenuation is 25.2 dB, the pass band insertion loss is 0.2 dB, and the quality factor Q value is 1.5×104. The device is of small size and simple structure, and it is easy to be integrated on a large scale. It has important application prospects for Ultra Wideband(UWB) communication.