PURPOSE: To extract only a partial shape from an assembly drawing which is read, to generate plural parts drawings, to maintain parts constitution at an inner part, to overlap shapes drawn on the plural parts drawings so as to set them to be parts constitution and to make one piece of assembly drawing.

CONSTITUTION: A picture segment processing part 63 segments an input picture from a picture input device 1 into plural pictures by using a inside/ outside polygon multiplex designation method, a picture data inquiry method and a segment/arc inquiry method. A picture information associating processing part 64 executes grouping, sequencing and indexing processings on the plural segmented picture. A picture information output processing part 68 gives transmission/nontransmission attributes to the plural segmented pictures and executes a clipping display processing and a superposing display processing. When the structured picture information is retrieved, a parts table can automatically be outputted and only the shapes of the parts numbers are eliminated on the parts in the assembly drawing so as to move them.