To print an overlay form of different contents in each page.

This device has a multi-overlay instructing part 303 which designates an overlay form to an optional printing job, a multi-overlay data preparing part 304 which prepares actual data for multi-overlay based on designated overlay information, a provisional printing data preparing part 305 which prepares provisional spool data for printing for overlay synthesis when multi- overlay is instructed, a page information controlling part 308 which acquires the page information of prepared overlay data and the page information of the printing data, a printing data synthesizing part 309 which refers to each acquired page information, synthesizes an actual printing job and the overlay data in each page and repeatedly executes them until the synthesis of the entire pages is completed, and a real printing data preparing part 311 which prepares printing job spool data that is actually processed by a printing part from synthetic data.