A storage apparatus providing a logical storage area for storing data to an external apparatus, includes a plurality of storage devices each providing a physical storage area for storing the data, the storage devices being different from each other in device property including data input/output performance, a capacity virtualization part managing the physical storage areas of the storage devices as unit physical storage areas each having a predetermined storage capacity and managing the unit physical storage areas in association with a plurality of unit logical storage areas forming the logical storage area, a tier controller managing the plurality of unit physical storage areas by classifying into a plurality of tiers the unit physical storage areas provided by the storage devices having the different device properties, and a redundant data management part managing redundant unit storage areas which are a plurality of the unit physical storage areas storing the same data. The data migration between the tiers is controlled according to, for example, an access frequency to the data from the external apparatus.