One aspect of the invention is a backup system that collectively performs the backup of data in a block form stored by a block recording device, and the back of data in a file form stored by a file recording device. According to the present invention, a backup system comprises: a first storage unit for storing first data using a first storage form; a second storage unit for storing second data using a second storage form; a backup storage unit for storing backup data for the first data and the second data; a storage form converter for converting into data for the second storage form the first data stored in the first storage form by the first storage unit; and a backup manager for copying into the backup storage unit the first data and the second data stored in the second storage form by the second storage unit.