Fixing device for medical use to non-invasively fix a marking device for medical use (22； 124), which has two or more marker elements (24； 128), to a body part (16) of a patient ( 14), in particular on a thigh, where the fixing device (20； 100； 122； 130) comprises a supporting body (46) that extends flat in two extension directions angularly oriented to each other (42, 44) , in its shape adaptable to the contour of the body part (16), in which the marking device (22； 124) was fixed or can be fixed, where the supporting body (46) can be elastically dilated on the surface of its extension and comprises a first expansion area (60； 132) and at least a second expansion area (62； 134), whose dilatability in at least one direction (42, 44) on the surface of the extension of the supporting body (46 ) is smaller than that of the first dilation area (60； 132), where the device fixing bracket (20； 100) comprises at least one fastener (84； 104) that is attached to the supporting body (46), and where the marking device (22) or a marking element of the marking device (22) is fixed or can be fixed with force drag and / or positive connection on one side of the clamping piece (84； 104) in the opposite direction to the supporting body (46).Dispositivo de fijación de uso médico para fijar de manera no invasiva un dispositivo de marcación de uso médico (22； 124), que presenta dos o más elementos marcadores (24； 128), a una parte del cuerpo (16) de un paciente (14), en particular en un muslo, donde el dispositivo de fijación (20； 100； 122； 130) comprende un cuerpo portante (46) que se extiende en forma plana en dos direcciones de extensión orientadas angularmente entre sí (42, 44), en su forma adaptable al contorno de la parte del cuerpo (16), en el que se fijó o puede fijarse el dispositivo de marcación (22； 124), en donde el cuerpo portante (46) puede dilatarse elásticamente en la superficie de su extensión y comprende una primera área de dilatación (60； 132) y al menos una segunda á
