To obtain a sheet guide cylinder low in structural expense ensuring the guidance of a sheet not generating the strike-through of a printed sheet by fixedly arranging a partition plate equipped with a fan possible to change over spraying air and suction air to a frame and providing a through-hole to the partition plate.

A plurality of fans 15 immobile with respect to a frame are provided to a cylinder on the end surface side thereof so as to be arranged in a symmetrically distributed state and connected to a voltage supply part in a circuit technical manner. The peripheral wall 13 of the cylinder supported in a rotatable manner has an air discharge opening 23. A closed guide plate is fixedly arranged to the frame within a range wherein the guidance of a sheet by the peripheral wall 13 in the cylinder is not performed toward the rising passage of a paper discharge device in order to improve efficiency. In this case, the peripheral wall 13 of the cylinder has a large number of openings 23.