To easily manufacture antennas in each of which a radiation element and a ground plate are arranged on the same plane without using etching.

This antenna manufacturing method for manufacturing a plurality of antennas in each of which the radiation element and the ground plate are arranged on the same plane, includes: a formation process 101 of supplying a sheet 10 including a base layer of the antenna, a separator, and an adhesive layer for adhering the separator to the base layer to form a plurality of conductor layers in the shapes of the radiation elements and the ground plates on the base layer; a punching process 102 of performing punching in the outer shape of the antenna from the side of the conductive layer so as to penetrate the base layer of the sheet and peel off punched residue of the outer shape of the antenna of the sheet from the separator; a cable connection process 104 of connecting a power supply cable to the radiation element and the ground plate; and a separation process 105 of separating the base layer from the separator. The processes are performed in order.