A storage apparatus includes a copy control unit for managing a copy session for copying an copy source data area in at least one of the first to the Mth copy source disk groups to an copy destination data area in a corresponding copy destination disk group, setting a first to an Mth copy session groups, each of the copy session groups including one or more copy sessions from the ith copy source disk group to the ith copy destination disk group as the copy session, and performing repeatedly a selection operation for cyclically selecting a copy session from each of the first to the Mth copy session groups in a predetermined sequence and a control operation for cyclically executing copy processing on a predetermined copy processing unit basis for the M copy sessions selected by the selection operation in a predetermined sequence for a prescribed number of times.