The radio wave receiver includes the metallic case body, the metallic rear case, and the antenna inside the case body. The screw portion is formed in the metal wall of the case body. The coupling resin member having an electrical insulating property is coupled to the rear case through a great number of fine irregularities formed in the metal wall thereof. The screw portion which engages with the screw portion is formed on the coupling resin member. The case body and the rear case are coupled to each other with the screw portions. The case body and the rear case are electrically insulated from each other by the electrical insulating function of the coupling resin member so as to improve receiving sensitivity of the antenna.