Abstract: A vehicle anti-theft device attachable to a steering wheel. The device is in the form of a wheel-like member having an inner disposed bight defining a space for admitting a rim of the steering wheel, the open portion of the bight having at least one pair of opposed slots for admitting a free end of a lock bar which is lockable by a lock. The device extends the size of the steering wheel along the radial and tangential directions, thereby increasing the size of the steering wheel, which will encounter obstacles with respect to the vehicle structure and the occupant attempting to rotate the steering wheel. In one embodiment, the device includes an elongated bight member having two pairs of opposed slots which are traversed by a U-shaped saddle member passing through the slots and defining a locking space about the rim of the wheel. A lock is associated with the saddle member for maintaining the saddle member in an engaged position with the bight member.