To secure satisfactory characteristics and performance of an antenna while securing thinness of the entire antenna and easy forming.

Slots are arranged and formed in a metallic foil part of an metallic foil-stuck insulating substrate, where the metallic foil is stuck to one face of the insulating substrate, to form a radio wave radiation metallic part 110, and a radio wave radiation substrate 100 with the insulating substrate as a radome 120 is provided. A hole 310 for feeding which pierces the center position of a metallic plate-stuck substrate where a metallic plate is stuck to one face of a dielectric substrate is formed, and this dielectric substrate surface is adhered to the surface of the radio wave radiation metallic part 110, and a waveguide forming substrate 220 with the dielectric substrate part as a waveguide 220 and with the metallic plate part as a metallic mount 210 is provided. The front end part of a feed line 400 is attached to the hole 310 for feeding to form a feed part 300. The hole 310 for feeding is secured free from over-cutting at the time of working, and satisfactory characteristics and performance are easily obtained without over-cutting.