PURPOSE: To provide a sheet feeder which is used as an intermediate magazine or buffer store part for sheet separation at high reliability.

CONSTITUTION: A sheet feeder B, designed as a buffer store part, comprises a magazine 24 comprising a base 26 for receiving vertically stacked sheets. An endless belt 18 which moves along an edge strip R of a sheet stack S is attached with a separating member 1, provided with a curved suction surface, with a plurality of spacers 11 following it. The edge sprit of the sheet at a bottom part is sucked to a curved suction surface and so bent downward as away from a remaining stack. The following spacer contacts on it, on which a remaining stack is supported. After the separating member passes by the edge strip, the edge strip contacts the lower surface of spacer, and entirely bent away from the remaining stack, and the endless belt 18 stands still for a short time at this position, so that the edge strip is supplied to a conveyor belt 35 from that position by an adjustable suction head 31.