An electronic file system includes a recording-medium drive for driving one of a first recording medium and a second recording medium, a terminal device outputting access requirements, and a carrier mechanism for setting one of the first recording medium and the second recording medium into the recording-medium drive in response to an access requirement outputted from the terminal device. The electronic file system also includes a controller connected between the terminal device and the carrier mechanism for processing access requirements outputted from the terminal device to reduce a number of times of setting operation of the carrier mechanism. The controller is arranged so that while a first page of read-out data is being indicated by the terminal devices subsequent pages are pre-read and stored in a short term, fast memory designated for this purpose. Pre-reading of subsequent pages is allocated to terminal devices which have the smallest sum of store times where store time is constituted at a time during which a respective page is stored in the short term memory.