1. An image density reproducing method in which density data for each pixel obtained by reading a document in a unit of a predetermined pixel using optical image reading means is processed to reproduce the density of the document, comprising the steps of: detecting, when an image of the read document is divided into image portions each including a predetermined number of pixels constituting a predetermined matrix, a position of a target pixel which is to be processed in said predetermined matrix; and subjecting, in accordance with gamma correction characteristics predetermined to correspond to each pixel position in said predetermined matrix, the density data corresponding to the target pixel to gamma correction on the basis of the position in said predetermined matrix of said target pixel.