To provide a graphic pattern forming method for a semiconductor EB device curtailed in the data quantity after EB processing without exerting influence to the images of the mask patterns in a series of optical lithography stage and RIE stage.

This graphic pattern forming method for the semiconductor EB device consists in forming an optical proximity effect correction pattern 15 applied on a projecting shape graphic pattern 11 partly in overlap to a rectangular shape near the apex of the projecting shape graphic pattern 11. In such a case, the projecting shape graphic pattern 11 and the optical proximity effect correction pattern 15 of the rectangular shape are subjected to conversion processing to a data format readable by a plotting device as separate data.