In a storage system, a storage apparatus has an encryption key generator and an encryption processor that encrypts data to be recorded in a storage region using an encryption key from the encryption key generator, and is able to change an encryption key for each divided region set in the storage region. A control apparatus has a logical volume setting unit that requests the encryption processor to set an individual divided region for each storage region set as a logical volume in the storage region of the storage apparatus and a data erasure processor that requests the encryption processor to change the encryption key used for encryption in the divided region corresponding to the logical volume to be erased.