A method for enhancing speed of incremental backup, a bridge device, and a storage system are provided. The method includes: regarding a predetermined location within the storage system, determining whether a record file exists; in response to the record file existing, determining whether any file needing to be compared exists; in response to said any file needing to be compared existing, comparing said any file needing to be compared with content of the record file to generate at least one comparison result, wherein said at least one comparison result indicates whether a set of attributes of said any file needing to be compared completely exist in the record file; according to said at least one comparison result, determining whether any difference is found; and in response to said any difference being not found, preventing triggering any backup from a source storage device to a target storage device.