Abstract: The invention relates to a fastening frame (3) for fastening a child seat (1) in motor vehicles that are provided with child seat anchoring elements (5), with which the vehicle is equipped and which are assigned to each vehicle seat while being joined in a fixed manner to the vehicle body and/or to the vehicle seat. Said fastening frame (3, 13) comprises a fastening section (23). Anchoring elements (24) for detachably anchoring the fastening frame (3, 13) to the child seat anchoring elements (5), which are joined in a fixed manner to the vehicle, are connected to one end of said fastening section, and a supporting section (8) is connected to the other end. This supporting section is supported in front of the vehicle seat on the vehicle floor (4) or on vehicle body parts and, when the fastening frame is mounted, the supporting section slopes downward toward the front.