PURPOSE: To perform the delivery of paper accurately piece by piece to the body side for duplex copying, by installing an aligning device which aligns the paper in a stacking part into a state capable of taking it out by a takeoff device.

CONSTITUTION: When a motor is driven, a side plate 40, to which a separating claw 36b is solidly attached, moves in a Y direction via a rack 44, whereby one side edge of paper P is trued up. Next, when another motor 43 is driven, a pressing plate 37 moves in an X direction via a rack 41, therefore the paper P has its tip engaged with both separating claws 36a and 36b and trued up in keeping the one end edge in a state of being trued up intact. And, when the specified number of sheets of the paper P are stacked in a state of being trued up on a push plate 33, this plate 33 goes up, and since the paper P is pressed by a feed roller 32, the paper P is accurately taken out piece by piece to a sensitive drum for its duplex copying by rotation of this roller 32.