A storage system capable of identifying all volumes to be audited is provided.Operation logs 3005 concerning the operations of volumes are associated with a time and stored in storage apparatuses 1400 and 1500, and a management computer 1100 collects information about these operation logs 3005, restores the status history of the operation logs 3005, sets, as an audit range, the operation logs 3005 including volumes with an audit period and audit target data stored therein, extracts the operation logs 3005 belonging to the audit range from the restored status history of the operation logs 3005, and transmits the extracted operation logs 3005 to a computer (requesting computer) 1000. As a result, all the audit target volumes can be identified.