In an AV-data transfer system, AV data stored in a RAID embedded in an AV server is supplied to a client personal computer connected to a network such as the Internet or an intranet by way of the network, and AV data output by the client personal computer is transmitted to the AV server through the network to be stored in the RAID. The AV server makes accesses to the RAID to write and read out data into and from the RAID. In addition to the AV server, the AV-data transfer system also includes another personal computer for exchanging AV data with the client personal computer and receiving a variety of commands from the client personal computer by way of the network in accordance with an FTP (File Transfer Protocol). As a result, it is possible to fast handle access requests made by a larger number of client personal computers.