1. An editing apparatus for editing a plurality of pages to array images thereon, comprising: a page selecting unit configured to select one of the plurality of pages as a first page for editing; a first display controlling unit that controls a display of images arranged in the first page selected by said page selecting unit, in a page area of page and evacuation areas included in an editing screen; a page image selecting unit configured to select at least one image from among the images arranged in the first page displayed in the page area included in the editing screen; a deletion instructing unit that instructs to delete the image selected by said page image selecting unit, from the first page; a holding unit that holds a predetermined number of images which are allowed to be arranged in each of the plurality of pages; a determining unit that determines whether the number of the images arranged in the first page other than the image instructed to be deleted by said deletion instructing unit corresponds to the predetermined number of the images which are allowed to be arranged in the first page, held by said holding unit; a second display controlling unit that controls a display of the image instructed to be deleted by said deletion instructing unit, on the editing screen in such a manner that the image instructed to be deleted by said deletion instructing unit is displayed in the evacuation area included in the editing screen and is no longer displayed in the page area included in the editing screen, if said determining unit determines that the number of the images arranged in the first page other than the image instructed to be deleted by said deletion instructing unit corresponds to the predetermined number of the images which are allowed to be arranged in the first page; an evacuated image selecting unit that selects at least one image from among the images displayed in the evacuation area included in the editing screen; an image addition instructing unit that instructs to additionally arrange the image selected by said evacuated image selecting unit, in a second page selected as the subject page of editing by said page selecting unit; and a third display controlling unit that controls a display of the image instructed to be additionally arranged by said addition instructing unit so that the image instructed to be additionally arranged by said addition instructing unit is displayed in the page area included in the editing screen and is no longer displayed in the evacuation area included in the editing screen.