In this paper, Deduplication is discussed as a green storage technology to improve the efficiency of network data transmission. Firstly, this paper introduces the concept of deduplication and what kinds of normal fields it can be used. Secondly, it explains the working principle of deduplication. Lastly, the method is implemented to improve the efficiency of network data transmission by software instead of improving the hardware system as before. It analyzes the process how to increase speed of network data transmission by using deduplication.