A portable radio device of a type having two-direction openable and closable enclosures that can effectively lessen influence on an antenna exerted by a hinge section is provided. A horizontal hinge section 5 for rotatably joining an upper enclosure 1 to a hinge enclosure 3 around a first shaft center includes a horizontal hinge anchor 52 electrically connected to a first metal part 13 disposed in the upper enclosure 1, a horizontal hinge plate 53 that is placed in the hinge enclosure 3 and that contains a conductive material, and a first hinge shaft 51 that electrically connects the horizontal hinge anchor 52 to the horizontal hinge plate 53 and that contains a conductive material interposed between an area from a substantial center to an end of a long side of a face along which the upper enclosure 1 and the hinge enclosure 3 face a direction of second shaft center (X). An electrical path length of the lateral hinge section 5 including the lateral hinge plate 53 and the first hinge shaft 51 corresponds to a predetermined value that is not a substantially constant multiple of λ/8.