PURPOSE: To provide a process device in a mimeograph device, in which dust does not invade into a process means.

CONSTITUTION: The process device 100 in a mimeograph device is provided with a master roll 1R, storing a roll-type heat sensitive mimeographing master 1, a process means, processing a master extracted out of the master roll 1R by a thermal head 3 and a platen roller 2 abutted against the thermal head 3 through the master 1, and cut members 4a, 4b, arranged at the downstream side of the process means and cutting a processed master 1a at a predetermined position. Further, the process device 100 is provided with a receiving means consisting of a lower cover 8, covering at least the master roll 1R and the process means excluding the feeding port 12 of a master transfer passage P, and an upper cover 7, free of opening and/or closing with respect to the lower cover 8.