An audio/video storage device using a hard disk speeds up the start of reproduction of an audio/video file and reduces power consumption and a noise level. A data recording/reproducing system of the present invention has a hard-disk drive and a flash memory device. When an audio/video file is recorded, the entirety of the file is stored into the hard-disk drive and a starting section of the file is stored into the flash memory device. When the file is reproduced, the reproduction is started from the starting section of the file that was stored into the flash memory device, and the remaining sections that follow the starting section are reproduced from an internal hard disk of the hard-disk drive.