There is disclosed a file management method in a log-structured file system for storing accesses to files that are sequentially performed by sequentially adding logs. A storage area of a storage medium is previously divided into a data area for storing a log including data of the file and a management area that can store management information related to the log stored in said data area for a plurality of entries. Then, the management information including a first number indicating the order of writing the entry is added and stored in the management area as a new entry.