an antenna holder to be mounted on a car body part of a motor vehicle having an opening , in particular a motor vehicle roof , having an antenna base and an anchoring device projecting beyond the antenna base , whose outer cross section is smaller than the opening cross section of the opening . the preassembled anchoring device includes an anchoring claw having a plurality of spreadable arms , a spreading element for spreading apart the arms and an actuating member for the approach of the spreading element to the antenna base while the spreading apart of the arms takes place .