Multipath routing protocol establishes multiple transmission paths between source node and destination node, which can not only transmit data in parallel, but also one as main path and others as backup paths. The paper proposed a multipath routing protocol PL_AOMDV with power controlling and load balancing based on AOMDV. In order to implement load balancing and prolong network lifetime, it allocates traffic bandwidth based on node remaining power and load status along the path. Appropriate power is used to transmit data packets. As Ad hoc network is complicated and changeable, the proposed protocol conducts periodical routing maintenance to adjust bandwidth allocation of traffic in time. Simulation experiment results show that the improved PL_AOMDV protocol achieves better performance in the aspects of load balancing and average node lifetime.