WRITE ONCE RECORDING DEVICE

An access device 1 internally includes a logical-physical empty capacity management part 16 for obtaining information of a remaining capacity on a write once memory from a write once recording device 2A. In addition, the write once recording device 2A internally includes a physical empty capacity management part 27 for managing a remaining capacity on the write once memory and notifying the access device of the capacity. Prior to recording of file data, the access device 1 can know an accurate remaining capacity of the write once recording device by: obtaining a remaining capacity of the write once memory from the write once recording device 2A; and comparing the capacity with a remaining capacity on an FAT to decide an actually-recordable remaining capacity for file data.