The data storage device includes a separator configured to separate data requested to write by clients into data chunks, an address translator configured to translate first addresses generated by the data chunks into second addresses as global addresses, a storage node mapper configured to map the second addresses to a plurality of storage nodes, and a data store unit configured to select a target storage node among the plurality of storage nodes and store the data chunks in the target storage node. The data chunks include a plurality of data input/output unit blocks. If other data chunks that are the same with the data chunks are pre-stored in the plurality of storage nodes, the data store unit is configured to establish links between the same pre-stored data chunks and the second addresses, rather than stores the data chunks in the plurality of storage nodes.