The invention relates to an air-diverting element with a flow-optimized contour for an air-conditioning system, in particular of a motor vehicle, which air-diverting element extends approximately perpendicular to an air flow direction. To divert an air flow through approximately 180° and at the same time nevertheless prevent pressure losses and disadvantageous acoustic effects, one end of the air-diverting element is adjoined by an approximately parabolic elongation which is situated opposite that side of the air-diverting element which faces away from the air flow direction.