Abstract: The invention relates to an arresting brake for a wheelchair, having a braking element which is articulated pivotably on a retaining element and, by pivoting a hand brake lever, can be pivoted into an arresting position in which the braking element bears, under pressure, on a wheelchair wheel or its tire. In order to provide a versatile arresting brake for wheelchairs, the invention proposes that the hand brake lever also be mounted on the retaining element, which is pivotably suspended on an adaptor which exhibits fastening device, for fixing it on the wheelchair frame, and a pivot pin which is located in the longitudinal direction of the wheelchair when the adaptor is mounted and about which the retaining element can be pivoted out of a positive locking catch position, which defines the braking function position, into a storage (rest) position located within the outer contour of the wheelchair.