The invention relates to a device for locking the chock (3) and the axial bearing housing (5) of a roll set as well as the roll change carriage (7) during rolling and during change of rolls. In that case provided at the roll housing (1) is a horizontally displaceable locking device (2) having locking elements (4, 6, 9) by way of which the locking device (2) for axial displacement of the roll is lockable to the roll chock (3) in order to fix the position of the axial bearing housing (5) with respect to the chock (3) of the roll or is lockable to the roll change carriage in the roll change position.