A swing hinge apparatus of a portable terminal is provided. In the portable terminal, a pair of housings is rotatably assembled while facing each other. The swing hinge apparatus includes a lower casing mounted and fixed to a first housing from among the pair of housings, a cam member mounted and fixed to a second housing from among the pair of housings and rotatably received in the lower casing, a guide groove formed on the lower casing and extending along a circumference, and a guide protrusion formed on a first surface of the cam member and moving along the guide groove according to rotation of the cam member, wherein both ends of the guide protrusion have inclined outer walls, both ends of the guide groove have inclined inner walls, and the guide protrusion is engaged with one of the inclined inner walls of the both ends of the guide groove, so as to limit a range of rotation of the cam member.