To provide a three-dimensinal(3D) simulation method capable of shortening plotting processing time by using the retrieval of primitive graphics for the attainment of various 3D simulation functions.

Information defining circumscribed rectangular parallelopiped C including all primitive graphics A, B constituting each equipment/installation is prepared in each equipment/installation and the primitive graphics of the equipment/installation included within a vidual field are collectively retrieved as a group of the equipment/installation unit by using the prepared information, so that the quantity of retrieving processing can be reduced. Since the simplification of a shape and the retrieval/ non-plotting of an unvisible equipment can be executed by using the information of the circumscribed rectangular parallelopiped C, the number of polygons to be plotted can be reduced and plotting processing time can be shortened.