Wireless sensor network is currently a hot research area of wireless communication system. In this paper, the optimum model of the wireless sensor network would be discussed; this can control natural disasters effectively and restore the loss of human. In the square area with fixed-side 100, place some sensor nodes whose coverage radius is10 in order to monitor the whole square. After careful calculation and comparison, proposed the reasonable scheme of how to place fewer nodes to cover the area as large as possible. Finally, I do the research of simulation and propose direction of optimization.