In this paper, we propose an efficient power saving protocol for multi-hop mobile ad hoc networks, called p-MANET. Our design is expected as a new foundation MAC layer power saving protocol. The main goals of p-MANET protocol are to reduce significant power consumption and transmission latency, and to achieve efficient power saving. Each mobile node in p-MANET only needs to become active during one beacon interval for every n interval, where n is the size of a super frame. Thus, efficient power saving is expected. p-MANET also yields low transmission latency because that every mobile node is aware of the active beacon intervals of its neighbors such that it can easily choose a neighbor in active mode or with the least remaining time to wake up to forward packets. Simulations are also conducted to show the efficiency of the proposed p-MANET.