An image printing apparatus, an image printing system, an image processing method and a memory medium are provided for preventing the image printing apparatus from being occupied for a long time by a single user, thereby enabling efficient utilization of the printing resources. Discrimination is made as to whether image formation is possible based on the image data transferred from a host apparatus, according to the printing condition based on such image data, and the image data are stored in a memory device in case the image formation is judged to be impossible. Preferably, even if image formation is possible, a discrimination is also made as to whether fully adequate image formation is possible. In addition, there may be formed a list of the images in order to enable judgment by a user of the images of all the received pages or, after the image forming operation, identification of the images of the pages for which the image formation is judged to be impossible.