The present invention provides a file management system and method, and a storage system that can prevent file-multiplexing in a storage apparatus, and efficiently use the storage capacity of the storage apparatus. The storage apparatus stores first management information for managing two or more kinds of classification list, each classification list including one or more keywords, and second management information for managing the kinds of classification list set for each of one or more users with regard to each of one or more tiers of their respective virtual file trees; and sends, in response to a request from a client apparatus to search the classification lists for a classification list set for a directory, the classification list set for the relevant user with regard to the tier matching the request to the client apparatus with reference to the first and second management information.