The invention belongs to the field of radar electronic communication and specifically relates to a receiving antenna. The antenna comprises a radio frequency coaxial semi-rigid cable, a reflection plate, a first outer conductor insulating support, a first outer conductor, a second outer conductor insulating support and a second outer conductor. The antenna further comprises a first inner conductor, a second inner conductor, a third inner conductor and a fourth inner conductor which are coaxially arranged with the radio frequency coaxial semi-rigid cable. The radio frequency coaxial semi-rigid cable, the inner conductors, the outer conductors and the insulating supports form an antenna module together. The antenna module is installed on an installation base. An antenna cover covers the antenna module, and the cover opening of the antenna cover and the installation base form a flange fixed matching. The radial fit clearance between the antenna cover and the antenna module is filled by foam supports. The receiving antenna solves the problem that the inner conductors of a long and thin structure are difficult to machine, and the machining and assembling precision of the inner conductors and the outer conductors are effectively ensured.