A method for controlling hierarchical storage including: a first step for storing first information relating to the association between the specific processes and the storage regions of the storage tiers; a second step for obtaining second information relating to the access operations of the specific processes as a function of time; a third step for obtaining third information relating to the amount of access to the storage regions as a function of time; and a fourth step for identifying the time of occurrence of a change in the amount of access, from the second information and the third information on the basis of the first information, and determining, according to the identified time of occurrence of the change in the amount of access, a transfer initiation time at which data in the storage regions is to be transferred between storage tiers.