PURPOSE: To obtain a document feeder provided with structure capable of reduc ing miscopying by easily correcting skew that is likely to occur in the case of feeding a thin paper document to a document platen by the document feeder.

CONSTITUTION: As for the document feeder provided with such attaching structure that it is integrated with an image forming device 1 by coupling a hinge part by a unit supporting board 3 fixed near the document platen 2 positioned on the upper surface of the image forming device 1; the unit supporting board 3 is provided with an attaching reference part 3A and a displacing supporting part 3B fixed at a position where its end in an extension direction is rocked with the reference part 3A as a fulcrum at positions, in parallel with the document platen 2, and the direction of the document fed to the document platen 2 is changed by rocking the supporting part 3B with respect to the reference part 3A.