When nodes of Distributed file system are extended over wide area network, network communication has a great influence on the node selection of Distributed file system. In this paper, an improved algorithm is proposed to decrease the transport time by reducing the scale of nodes. This algorithm adopts the law of universal gravitation, which gives strategy of node movement. Meanwhile, to overcome premature or local-best solution, the theory of overcoming premature is referred, and then node can depart for a more suitable cluster. Theoretical proof shows the algorithm converges and has the top limit in the time complexity. Furthermore, experiment results give the availability and efficiency of the algorithm.