This paper feeder brings the uppermost paper sheet of a plurality of stacked paper sheets into contact with paper feed rollers and feeds out the paper sheet in a paper feeding direction by the drive thereof. Side fences for guiding both side edges of the paper sheet on a paper feeding table are provided with a pair of blowing units for blowing air to both side edges of the paper sheet, whose air quantity can be controlled independently of each other. When skewing occurs, the blowing units are controlled to blow a larger quantity of air to the paper side edge having larger friction against a lower paper sheet as compared with the quantity of air to the other paper side edge. In paper feeding, problems such as skewing, multi-feeding and idle feeding can be addressed.