In order to improve a windbreak device for motor vehicles, in particular for cabriolet vehicles, comprising a windbreak base which can be mounted such that it is fixed to the vehicle and on which a wind deflector which extends in a wind deflector surface can be mounted so as to move between an active position and an inactive position, and a drive device for moving the wind deflector between the inactive and the active position and vice versa, in such a way that the said windbreak device can be operated in as optimum a manner as possible, it is proposed that the drive device can be supplied with power from an on-board electrical system of the motor vehicle by means of a power transmission device, and that the power transmission device comprises a first element which is disposed on the windbreak base, and a second element which is disposed on a side wall of the body of the motor vehicle, the said elements transferring power from the on-board electrical system of the motor vehicle to the drive device which is disposed on the windbreak base when the windbreak device is mounted on the motor vehicle in a functional position.