Abstract: It is significant to research how to use the limited power efficiently for the energy contained wireless sensor networks.This paper proposed a tasks-driven feedback dynamic voltage scaling algorithm (FB-DVS) that based on the multihop routing and easily changed topology.FB-DVS could scale the working frequency and voltage levels dynamically according to the workload of sensor node, and fix the errors through feedback scheme and reduce the node′s power consumption at the premise of real-time tasks.The results of simulation indicated that the improved algorithm could effectively reduce the energy consumption and prolong the life of wireless sensor networks.