To provide a paper feeding device capable of preventing overlapped carrying of media to be printed and easily changing the size of a medium to be printed.

A paper feeding device B freely attached/detached from an image forming device A includes a feed roller 1 for taking out a plurality of media C one by one, a connection roller 2, an in-feed roller 3 and a register roller 4. The feed roller 1 and the connection roller 2 are rotated/stopped together at the same speed, the in-feed roller 3 and the register roller 4 are independently rotated/stopped and a linear speed of the in-feed roller 3 is made faster than those of the feed roller 1 and the connection roller 2. A distance between the feed roller 1 and the in-feed roller 3 is set smaller over twice than the feeding direction length of a minimum size medium to be printed and thus the feed roller 1 is reverse-rotated.