FIELD: road trains. SUBSTANCE: road train with a movable rotary support of the tractor contains a two-axle frame tractor, on the frame of which the semi-trailer rests through a turntable. The turntable is connected to the semi-trailer frame by means of a pivot pin, and is connected to the tractor frame by a longitudinally movable connection relative to the tractor. A support is installed on the tractor frame, movable in the longitudinal direction relative to this frame, and pivotally connected to the turntable. The movable support is connected to the tractor frame by means of a double-acting power cylinder, the body of which is fixed to the tractor frame in front of the movable support along the road train and is located coaxially with the longitudinal axis of the tractor. A working fluid distributor is attached to the lower part of the turntable, connecting the hydraulic system of the tractor with the piston and rod cavities of the double-acting power cylinder through hydraulic lines, and its spool is kinematically connected to the king pin. EFFECT: reduction in the overall length of the road train is achieved when moving along a straight path and on turns by maintaining the minimum required distance between the tractor cab and the towed semi-trailer. 1 cl, 3 dwg.