To provide a roll stop ring of a rolling machine having a simple and compact structure capable of solving problems such as installation spaces, maintenance, inspection.

The roll stop ring 10 of the rolling machine, which fixes and releases a roll 13 having a roll neck groove part 12 with a hollow axis edge part to a bearing 11 for fixing to a housing of the rolling machine, is fixed to a fixing pin 15, which is set at the outer edge part to the axis direction of the bearing 11, to be movable in the axis direction of the roll 13. Furthermore, it has a pair of half stop ring main bodies 16, 17 divided and placed oppositely, and capable of opening and closing with the fixing pin 15 as a supporting point, and several pressing members 38 arranged on a pair of half stop ring main bodies 16, 17 and capable of moving to the axis direction of the roll 13. The roll 13 is fixed to the bearing 11 by moving the pressing members 38 forward in the condition of engagement to the roll neck groove part 12 when the pair of half stop ring main bodies 16, 17 are closed.