The centroid algorithm is a widely used localization algorithm in wireless sensor networks (WSNs). Aiming at the problem of low localization precision of the centroid algorithm, a region-division-based localization strategy (RDLS) is proposed in this paper. However, the localization performance of RDLS could be degraded in presence of disturbance. Another optimal region selection strategy based on RDLS (ORSS-RDLS) is also proposed to address this issue. In order to test the performance of proposed strategies, several numerical simulations have been carried out. Compared with the traditional centroid algorithm, the proposed strategies show many advantages such as lower localization error, less time consumption, better localization stability and so on.