To provide a three-dimensional CAD system by which the kind and amount of chemical substance are easily grasped without imposing unnecessary burden on an enterprise and a product is efficiently designed and developed.

The three-dimensional CAD system comprises: a design means for stereoscopically designing the product; a first arithmetic means for calculating the volume of each raw material in the product which is designed by the design means; a database for holding information concerning the content of each chemical substance contained in each unit volume of the raw materials; and a second arithmetic means for calculating the content of each chemical substance contained in the designed product, based on the volume of each raw material, while referring to the database.