Disclosed is a disk control apparatus with excellent scalability realized on the same architecture, in high quality and reliability, regardless of its scale. Each of a plurality of channel interface units and a cache memory unit as well as each of a plurality of disk interface units and the cache memory unit are connected through a switch and a data path network (solid line) in each disk control cluster. Each switch provided outside each disk control cluster is connected to the switch in each disk control cluster through the data path network. A resource management unit is provided outside each disk control cluster and the resource management unit is connected to each of the plurality of channel interface units/disk interface units, as well as to the cache memory unit in each disk control cluster. The resource management unit is also connected to each switch provided outside each disk control cluster through a resource management network (dotted line).