PURPOSE: To keep lower the humidity in a dampproof paper case by disposing a paper cassette for storing paper and a paper feed device in the dampproof paper case and providing a heater.

CONSTITUTION: Paper 2 fed out sheet by sheet by a paper supply roll 4 is delivered from a paper discharge port 1 to a paper transport apparatus in a copying machine. As the paper 2 is stored in a dampproof paper case 12 where air is warmed up by a heater 13 to lower the relative humidity, even if the relative humidity of the outside of the dampproof paper case 12 becomes higher, the paper is stored with the moisture kept lower. Furthermore, the paper hardly absorbs moisture in the outside air during transportation for a little time required reaching a heat fixing roll. Therefore, even if the paper contacts the heat fixing roll, very little moisture is lost, so that the paper is little curled and the occurrence of a paper jam in the copying machine is remarkably reduced.