An air-guiding device (7) can be arranged in a wheel house of a motor vehicle and has a plurality of slats (12). Each slat (12) has at least one first region (11.1, 11.3) with a first profile and at least one second region (11.2, 11.4) with a second profile. The respective profile of the respective region (11) of the respective slat (12) is matched to the respective flow conditions present by a respective shaping and a respective angle of attack. Therefore an air stream approaching the slats (12) has to overcome a reduced aerodynamic drag when passing through the respective slats (12).