A circular polarization antenna structure with a dual-layer ceramic includes a first hard dielectric body, a first metal layer, a grounding layer, an antenna feed pin, a second hard dielectric body, a second metal layer and an adhesive element. The first metal layer and the grounding layer dispose on a top surface and a bottom surface of the first hard dielectric body. The antenna feed pin passes through the through hole of the first hard dielectric body, the top side of the antenna feed pin is fixed on the top surface of the first hard dielectric body, and the bottom side of the antenna feed pin extends outwards from the bottom surface of the first hard dielectric body. The second hard dielectric body disposes above the top side of the first hard dielectric body. The second metal layer disposes on the top surface of the second hard dielectric body.