An antitheft device for attachment to a steering wheel of an automobile comprising an elongated body member having two parallel passageways extending in a longitudinal direction. A first hook is secured to the body member for engagement with a portion of the steering wheel. The first hook engages the wheel from the inside of the rim, with the body member extending outward beyond the periphery of the steering wheel, an elongated rod member, adapted to move in telescopic fashion in one of two passageways formed in the body member, and extending longitudinally therein. A second hook, secured to the rod member, engages the inside portion of the steering wheel at a point diametrically opposed to that of the first hook. A second elongated rod member is adapted to extend in telescopic fashion in a direction opposite to that of the other rod member. A lock assembly is disposed within the body member for engaging the rods within passageways of the body member, allowing the rod members to extend with respect to the body member, and to be locked at any of a plurality of positions.