PURPOSE: To perform fast continuous transfer and improve printing efficiency by selecting photosensitive bodies which are ready to transfer successively with the output of a signal generating means, and operating them in parallel at mutually different timing.

CONSTITUTION: When a print command is outputted, a paper feed table 19 operates to start feeding paper 18, which is sent upward and downward selectively through a separation pawl 20. The paper 18 sent upward is reduced in speed along a roller 21 and a conveyance guide 22 to reach a gap between a roller 23 and a photosensitive body 27 to transfer a toner image written with a laser beam, and the paper is sent in the order of a guide 24 and a paper discharge roller 25 and stacked on a tray 26. Paper sent downward by the pawl 26 is handled similarly. The paper 18 is supplied continuously to an upper and a lower photosensitive body 27 by the pawl 20 and guides 22 with a speed reduction latch, so the throughput is doubled as compared with one photosensitive body 27.