The storage system includes a plurality of storage devices and a controller that manages a virtual volume including a plurality of virtual storage areas, and manages a storage pool including a plurality of storage areas prepared on the storage devices in order to allocate a storage area in the storage pool to the virtual volume in response to receiving a write command to the virtual volume for writing data corresponding to the write command. In response to receiving a specific write command to write a specific data to a first virtual storage area to which a first storage area is allocated, the controller releases the first storage area from the first virtual storage area.