The invention relates to a fixing device (2) for a wall-hung sanitaryware item (1). The fixing device (2) has a holder (11) for mounting the fixing device (2) on a wall (15). On the holder (11) there is movably arranged a supporting element (12), in which an engagement element (13) is supported and which is movable relative to the holder (11) for insertion into an opening (7) in the sanitaryware item (1). In order to allow quick and easy demounting of the sanitaryware item (1), according to the invention the supporting element (12) is movable relative to the holder (11) transversely with respect to an insertion direction (E) of the fixing device (2) into the opening (7) in the sanitaryware item (1). (Figure 1)
