The present invention relates to a hinge device for portable terminal, characterized by including: a stationary cam mounted on one side of the hull part and the hinge part; a movable cam, mounted on the other side of the hull part and the hinge part to make the hinge part switch; a spring, making the movable cam elastically contacting with the stationary cam. A cam profile is made up of the following sections formed at one side of the contact surface: a first section, wherein the spring is compressed and the movable cam rotates with the stationary cam when the hinge part is initially open; a second section, wherein the spring keeps the compressed state and the movable cam rotates or reposes relative to the stationary cam; a third section, wherein the spring resumes and the movable cam keeps still after rotating relative to the stationary cam; a fourth section, when the force is applied to the direction of the hinge part opening, the spring is compressed and the movable cam rotates with the stationary cam; when the outside force is released, the spring restores and the movable cam rotates in the opposite direction and returns to the resting position. The invention can not only prevent the deformation and the disrepair of the products but also makes for the miniaturization of the hinge device. |