The invention relates to a device for attaching a flat and flexible band (2) on at least one bone part (3), comprising said band having two end portions (2, 2''), a rigid base body (5) crossed by an opening (11), and a retaining part (12) that can be inserted in said opening. The retaining part (12) is at least partially in the shape of a squeezable wedge comprising a central bore (13) for passage of said end portions (2', 2'') facing the flexible band, said bore (13) having a transverse cross-section that can be deformed between a first cross-section (SI) for free passage of the end portions (2', 2'') when the part has not been inserted in the opening and a second cross-section (S2) for locking said end portions by compression when the part is entirely or substantially entirely inserted in the opening.