Abstract: A roll bar protection system for motor vehicles comprising an outer box profile forming a case for the components of the roll bar protection system, being mounted firmly on the vehicle, an inner box profile, able to move in the outer box profile via guide elements which is designed as a roll bar and accommodates a fast drive for its extension into the upper end protection position in event of danger, and a drive arrangement for a continuous movement of the inner box profile, consisting of an electric motor/gearing arrangement with a threaded spindle of predetermined length, as well as a tie-bar which can be moved in the outer box profile, having a nut for engagement with the threaded spindle, and which is detachably connected to the inner box profile.