PURPOSE: To simplify a synthesizing copying work by independently validating a trimming mode and a masking mode in an area stored in an area storing circuit at respective copying steps in the continuous copyings of twice to execute a continuous synthesizing copying.

CONSTITUTION: When a synthesizing copying processing is selected by turning on a synthesizing copy key 12, only a left original 10 is read out and the range of areas (a)W(d) is copied. After the copying, paper is stocked on an intermediate tray, and then an original 11 is read out on an original platen to synthesize a graphic 101. A mode set up at the time of input data and the mode out of the trimming and masking modes is validated in an initial copying process, and in a 2nd process, the other mode is validated, the paper completing the initial copying process is led into the intermediate tray. At the 2nd process, the paper stocked on the intermediate tray is led into the copying process part. Consequently, the left original 10 can be trimmed and the right original can by masked.