PURPOSE: To define the location of printed matter at each user in making a relationship between a sorting shelf and a user or the printed matter so as to be understood after sorting at each printed matter at the time of using a printer unit for many users in common by connecting plural personal computers to a local area network.

CONSTITUTION: The same contents are transmitted to all personal computers 21 to 2n through a transmitting circuit 18 from a comparator 14, but such a fact that printing has finished is made so as to be individually transmitted to each personal computer of users who request the printing. When each photo detector of a detecting part 16 detects such a fact that prints are hard to be stored any longer ineach shelf of a sorting shelf 12, a control part 19 stops any printing operation of a printer part 11 at once. In addition, this detection contents are transmitted to the personal computers from the comparator 14 through the transmitting circuit 18 and an LAN 20, and when the user takes out the printed matter from the shelf alloted to oneself of the sorting shelf, the control part 19 makes the printer part 11 reopen its printing on the basis of the detected result, and thus the printed matter is put in the shelf.