A process for preparing an ink-jet system printing plate, wherein an image is formed according to a hot melt type ink-jet system by heat-melting an ink composition that is solid at ordinary temperature, spraying droplets of the ink composition in a hot melt state from nozzles onto an intermediate transferrer to form an image, and contact-transferring the image on the intermediate transferrer to an image receiving layer of a planographic printing plate precursor, the image receiving layer being provided on a water-resistive support and containing zinc oxide and a binder resin, and thereafter, a nonimage area of the image receiving layer is desensitized by chemical reaction treatment to prepare a planographic printing plate.