The invention provides a multi-movable-duplicate mechanism applied to distributed storage and an access method thereof, which are applicable to a distributed storage system with frequent reading operation. The dynamic duplicate access method is located on a metadata server of the distributed storage system, and the metadata server comprises a data node information maintenance module, a route analysis module, a user request processing module and a dynamic duplicate management module. A multi-movable-duplicate mechanism is provided, so that any duplicate in the system can be accessed by users at will, and the system reliability and input/output throughput can be improved; aiming at different application environments and user requirements, the quantity and the storage position of the duplicates can be dynamically adjusted, and the response speed of the system and the data flow transmission can be accelerated; and since the new duplicate has timeliness, the system can be enabled to rapidly respond to the access of the user, the space of a disc can also be saved, the resource waste can be avoided, and the system capacity can be increased.