An element damage determination unit calculates a cumulative value of a damage value using a Manson-Coffin law for a plurality of finite elements of a continuum based on a result of a stress/distortion analyzing process, and determines whether or not the cumulative value of the damage value is equal to or exceeds a threshold. A calculation unit obtains first correspondence information indicating the correspondence between the number of cycles of a load and a growth rate of a crack occurring in the continuum based on the determination result. A Manson-Coffin law change unit changes a Manson-Coffin law based on the first correspondence information and second correspondence information indicating the correspondence between an actual measurement value of the number of cycles of a load applied to the continuum and an actual measurement value of the growth rate of a crack occurring in the continuum at that time.