By using a folded conducting wall, the size of the microstrip antenna can be reduced and the beamwidth of the radiation pattern can be expanded. A new type of folded conducting wall is designed to decrease the manufacture difficulty and homologous costs. And a wide beamwidth right hand circularly polarized microstrip antenna based on this new type of the folded conducting wall is designed at L1 band. The simulation and measurement results show that this antenna has the advantages of small size, wide beamwidth and low cost.