An electrophotographic printing original plate is disclosed, which comprises an electroconductive support material and an electrophotographic photosensitive layer formed thereon, which electrophotographic photosensitive layer comprises (i) a charge generation layer consisting essentially of a particular azo pigment serving as a charge generating material and (ii) a charge transport layer consisting essentially of a charge transporting material and an alkali-soluble resin; and an electrophotographic printing plate making process using the above printing original plate is also disclosed, which comprises the steps of electrically charging uniformly the above printing original plate, exposing the charged printing original plate to optical images to form latent electrostatic images thereon, developing the latent electrostatic images with toner, fixing the toner images to the printing original plate, and removing the electrophotographic photosensitive layer portions corresponding to the non-image areas of the printing original plate by dissolving the photosensitive layer portions in a dissolving liquid, thereby making a printing plate.