A rear spoiler device for a vehicle with at least one rear door includes at least one lateral air-deflector element and a roof air-deflector element that can be adjusted between a default position and a travel position for contour extension and aerodynamic air conduction when the rear door is closed. The device comprises a wing, which has a first swivel joint to enable pivotable fastening to the rear door. The wing is adjustably attached to the lateral air-deflector element via at least one second swivel joint. At least one locking device is provided for locking the lateral air-deflector element with the wing. A coupling device is provided for coupling an adjustment of the locking device to the adjustment of the roof air-deflector element.