PURPOSE: To reduce conventional assembly processes by enabling manufacture only with molding by connecting an amplifier circuit part, etc., to a ground electrode in advance.

CONSTITUTION: This antenna unit is constituted by sealing an antenna electrode 1 equipped with a power feeding part 4, ground electrode 3 faced through an insulating layer 2 to the electrode 1 and amplifier circuit part 10 adjacent to the electrode 3 into a resin radome 7. Therefore, assembly parts such as screws required conventionally are unnecessitated. Besides, since the antenna unit can be manufactured only with molding, the assembly processes can be reduced and further, since the insulating layer 2 between the electrodes 2 and 3 is formed by resin, the antenna unit can be manufactured without requiring any printed wiring board for antenna element. On the other hand, since a metallic chassis 11 for covering the circuit part 10 is provided at the circuit part 10, external radio waves to affect the circuit part 10 can be cut off. Further, since a fitting member 12 is provided to fit the radome 7 to external equipment, the antenna unit can be easily fitted to the external equipment.