A communication terminal device includes a printed wiring board disposed in a casing, a feed pattern provided on a main surface of the printed wiring board, a radiation plate including a substantially planar radiation portion substantially perpendicular to the main surface of the printed wiring board and a lead portion connecting the radiation portion to the feed pattern, and a component mounted on the main surface of the printed wiring board to overlap the lead portion when the main surface of the printed wiring board is viewed from above, the component including a conductive material, a magnetic material and/or a dielectric material. The radiation portion is connected to the lead portion at a side spaced away from the main surface of the printed wiring board, and an area of the lead portion is located at a predetermined distance from the main surface of the printed wiring board.