Recording devices are disclosed having data storage units using disk-shaped storage media, data allocation storage units for storing allocation information of each stored data, and control units for writing and reading data using the allocation information in the data allocation storage, and also have use status storage units for storing use status information indicating each storage area in the data storage units is a valid area having data written therein or an invalid area having no data written therein. If the control units receive a read request for the data stored in the data storage units, the control units select only data of valid areas using the use status information in the use status storage units and read out the data.