To smoothly set a proper center distance in the case of separately carrying a piece of sheet materials by fixing the center distance between a carrier rotor and a separation rotor on a paper feeding device having the normally rotating carrier rotor and the reversely rotating separation rotor and to separately carry the sheet materials one by one by a sheet material separating part constituted of these both rotors.

It is possible to optionally select a first paper feeding mode to feed paper while automatically adjusting a center distance by center distance variation means 224-228 and a control means 1000 for each of sheet materials and a second paper feeding mode to feed paper by fixing the center distance on this device, and it is possible to carry out center distance setting adjusting motion to display a setting value of the center distance in accordance with a detection result on a display part 900 by detecting the center distance automatically adjusted at the time of feeding one or an optional plural number of the sheet materials in the first paper feeding mode at the time of setting the center distance at the time of selecting the second paper feeding mode.