To improve peelability from a conveyance means of sucked and conveyed paper, in a double-side printing device.

This double-side printing device 1 includes a first printing part 3 for printing on one surface of paper P1, a storing part 5 conveyed with paper P2 printed on one surface and storing a plurality of conveyed-in sheets of paper P2 in mutually overlapped states at prescribed intervals, and a second printing part 7 for printing on the other surface of the paper P2 conveyed out of the storing part 5. The storing part 5 includes a first conveyance means 51 for successively sucking and holding the paper P2 printed on one surface and conveying the paper P2 to a conveying-in position to be a paper peeling position in the storing part 5, and atmosphere opening mechanisms 5f and 5g for opening part of the surface on the first conveyance means 51 side of the paper P2 conveyed to the conveying-in position to the atmosphere, when the paper P2 is peeled from at least the first conveyance means 51.