With the development of modern wireless communication system, some specific higher requirements on the antenna are put forward. In order to meet the system requirements for wide beam radiation, an S-band wide beam circular polarized antenna is proposed. Additional parasitic patches are added on the radiation patch antenna in broadening the bandwidth of the antenna. And the metalized via is adopted to achieve unilateral short circuit. The purpose of miniaturization of the antenna design is therefore achieved. The sequential rotation method combined with multi-point feeding technology is utilized to obtain a broad band microstrip antenna wide beam circular polarized radiation. The structure parameters of antenna are designed according to theoretical analysis and High Frequency Structure Simulator(HFSS) software. The simulation results are in good agreement with the test results.