To accurately calculate a young's modulus, taking nonlinearity of the young's modulus of a resin material into account.

An approximation model creation and storing means 10 has a a means 11 for setting and storing initial conditions for various kinds of analyses, a means 12 for setting forced displacement, at shape deformation, of a structure tightened by a bolt or the like based on a warpage-deformation of the structure after infection molding, and a means 13 for recalculating the Young's modulus of the structure, based on a stress condition inside the structure and a stress-strain relation of a resin material constituting the structure. An analyzing means 20 is provided with a warpage analyzing means 21, a structure analyzing means 22 and a characteristic value analyzing means 23 to conduct corresponding analysis in each. A measuring means 30 has a means for applying load to the structure, a means 31 for measuring the warpage displacement after the injection molding and a displacement at load application, a means 32 for measuring the vibration characteristic of the structure, and the like. Various kinds of data are input or selected by an input device 1, various kinds of condition settings or analyzed results are output by an output device 3, and an execution command within a system is processed by an execution commanding device 2.