An exemplary storage apparatus of the invention includes storage devices for storing data of block I/O commands and file I/O commands and a controller including a block cache area and a file cache area. The controller creates block I/O commands from file I/O commands and accesses the storage devices in accordance with the created block I/O commands. In a case where the file cache area is lacking an area to cache first data of a received first file I/O command, the controller chooses one of a first cache method that newly creates a free area in the file cache area to cache the first data in the file cache area and a second cache method that caches the first data in the block cache area without caching the first data in the file cache area.