A computer-implemented method for optimizing a structure having two or more components, said method comprising the steps of: inputting an initial value of a wall thickness of each component of said structure; calculating an actual rigidity value of the structure on the basis of the inputted initial value of the wall thickness of each component of said structure; calculating an optimum value (OPT-T) of the wall thickness of each of said components on the basis of a sensitivity analysis result in order to make the calculated actual rigidity value of the structure close to a required rigidity value of said structure; selecting a standard wall thickness value (STD-T) closest to said optimum wall thickness value (OPT-T) for each of said components from a database storing standard wall thickness values; setting said wall thickness value of each of said components of said structure to said selected standard wall thickness value (STD-T); calculating a rigidity value of said structure on the basis of said selected standard wall thickness value; comparatively displaying the rigidity value of said structure calculated on the basis of said selected standard wall thickness value (STD-T) and the rigidity value of said structure calculated on the basis of said optimum wall thickness value (OPT-T) for each of said components as a list to enable the comparison of the values; calculating a difference in the rigidity value between said actual rigidity value and said rigidity value of said structure on the basis of said optimum wall thickness value (OPT-T) of each of said components; calculating a difference in the rigidity value between said rigidity value of said structure calculated on the basis of said optimum wall thickness value and said rigidity value of said structure calculated on the basis of said standard wall thickness value (STD-T); comparatively displaying the calculated differences in rigidity value for each of said components as a list on display means to enable the comparison of the values, calculating a difference (DIF-T) in a value between said initial wall thickness value and said optimum wall thickness value (OPT-T) obtained by said optimizing calculation for each of said components; calculating a difference value (SDIF-T) between said optimum wall thickness value (OPT-T) and said selected standard wall thickness value (STD-T) for each of said components; displaying the calculated wall thickness differences (DIF-T, SDIF-T) in value for each of said components as a list on display means to enable the comparison of the values; and, dependent on a quantity of at least one calculated difference value optimizing the structure only by changing a wall thickness value of each component of the structure or by changing the configuration of the structure. inputting an initial value of a wall thickness of each component of said structure; calculating an actual rigidity value of the structure on the basis of the inputted initial value of the wall thickness of each component of said structure; calculating an optimum value (OPT-T) of the wall thickness of each of said components on the basis of a sensitivity analysis result in order to make the calculated actual rigidity value of the structure close to a required rigidity value of said structure; selecting a standard wall thickness value (STD-T) closest to said optimum wall thickness value (OPT-T) for each of said components from a database storing standard wall thickness values; comparatively displaying the rigidity value of said structure calculated on the basis of said selected standard wall thickness value (STD-T) and the rigidity value of said structure calculated on the basis of said optimum wall thickness value (OPT-T) for each of said components as a list to enable the comparison of the values; calculating a difference in the rigidity value between said actual rigidity value and said rigidity value of said structure on the basis of said optimum wall thickness value (OPT-T) of each of said components; calculating a difference in the rigidity value between said rigidity value of said structure calculated on the basis of said optimum wall thickness value and said rigidity value of said structure calculated on the basis of said standard wall thickness value (STD-T); comparatively displaying the calculated differences in rigidity value for each of said components as a list on display means to enable the comparison of the values, calculating a difference (DIF-T) in a value between said initial wall thickness value and said optimum wall thickness value (OPT-T) obtained by said optimizing calculation for each of said components; calculating a difference value (SDIF-T) between said optimum wall thickness value (OPT-T) and said selected standard wall thickness value (STD-T) for each of said components; displaying the calculated wall thickness differences (DIF-T, SDIF-T) in value for each of said components as a list on display means to enable the comparison of the values;