To provide a device that is for quick mounting and dismounting of a blanket strip of a rotary cutting anvil cylinder.

The device comprises a locking and unlocking element disposed in a groove 5 cut in a circumference of a cylinder body 2 of the anvil cylinder, and the groove 5 extends through an overall width of the cylinder body 2. The locking and unlocking element comprises a detachable slider 9 movable in the groove 5. The detachable slider 9 includes a guide groove 10 and grooves 11 and 11a of linear cam shape. A roller fixed to at least one jaw portion is fitted in the groove, and the jaw portion is detachable so as to act on at least one end of the blanket strip. The detachable slider 9 operates by a traction device 44, and the traction device comprises an adjusting screw 49 threaded into a nut 55 attached to a lower portion of the detachable slider 9.