A positioning device for supporting a portable computer that includes a base member for placing on a horizontal surface, a support plate for supporting the portable computer at an inclined position relative to the base member, a hinge that rotatably connects the base member to the support plate so that the support plate can be rotated between multiple angular positions relative to the base member, and a lock mechanism for selectively fixing the angular position between the base member and the support plate. The portable computer, which includes a base housing having a front and rear end, a flat panel display rotatably attached to the rear end of the base housing, and a keyboard attached to a top surface of the base housing, can be supported in an inclined position directly by a support member that is rotatably attached to the front end of the base housing so that the support member can be rotated between multiple angular positions relative to the base housing, where a lock mechanism selectively fixes the angular position between the support member and the base housing so that the support member supports the base housing at an inclined position.