A biaxial hinge mechanism includes: an opening/closing support section projected toward an outer side of a casing; an opening/closing shaft supported on the opening/closing support section; an outer cover provided to be fixed to the casing so as to hide the opening/closing support section and the opening/closing shaft; a hinge base supported on the opening/closing shaft so as to be rotatable relative to the casing, with the opening/closing shaft as a center axis of rotation; a rotation-restricting section operable to restrict a rotation angle of the hinge base to within a predetermined range; a rotating shaft supported on the hinge base and provided in a direction orthogonal to the opening/closing shaft; and a rotating support section supported on the rotating shaft so as to be rotatable relative to the hinge base, with the rotating shaft as a center axis of rotation.