This image reading apparatus includes an image reading unit, an average-density calculation unit, a statistical processing unit, and a blank-page determination unit. The image reading unit reads an original image and outputs image data of the original image. The average-density calculation unit calculates an average density value of block image data for a plurality of block images, which are obtained by dividing the original image, based on the image data output from the image reading unit. The statistical processing unit determines a characteristic value of the average density value distribution associated with the block images. The blank-page determination unit determines whether or not the original image is a blank image based on the characteristic value determined by the statistical processing unit.