Metamaterials and metasurfaces are widely used in electromagnetic wave control due to their special properties that natural materials do not possess.Aiming at the application requirements of broadband,high-efficiency and miniaturization of polarization converters,a dual-polarization converter based on broadband and high-efficiency reflective metasurface is designed.Based on the principle of polarization control of elect romagnetic wave,a periodic array metasurface of circularly truncated square patch is designed to achieve efficient linear polarization and circular polarization conversion in a single b roadband on the basis of the two-angle truncated square patch.The results show that the polarization conversion ratio (PCR) of the polarization converter exceeds 90% in the frequency band range from 6.850 GHz to 11.050 GHz,and performance can be maintained within the range of incident angle less than or equal to 45°,covering the whole X-band to realize the linear polarization conversion with high efficiency and wide incident angle.The axial ratio (AR) is less than 3 dB in the frequency range from 6.225 GHz to 6.402 GHz and range from 12.562 GHz to 13.472 GHz, which realizes high-efficiency circular polarization conversion.In addition,th e metasurface has the advantages of simple structure,wide incident angle and convenient processing,which can meet the app lication needs in the fields of microwave communication,microscopic imaging and so on.