A method for optimizing a structure of an industrial product includes selecting control factors from among manufacturing parameters affecting a target characteristic, which is scheduled to be manufactured by a sequence of manufacturing processes; setting levels to the respective control factors; selecting a reference characteristic having a trade-off relation with the target characteristic from among characteristics of the structure; setting a reference value to the reference characteristic; selecting a prior adjustment factor affecting the reference characteristic; creating conditions for experiments assigning combinations of the levels to the respective control factors; determining an adjustment value of the prior adjustment factor so that each of characteristic values of the reference characteristic obtained by the experiments conforms substantially to the reference value; and determining experimental characteristic values of the target characteristic using the adjustment value.