Ad Hoc network is more convenient and cheaper than the networks with infrastructure in the usage and setup. As to wire network, the router and the terminals are also existed in Ad Hoc network. Compared with the roles of nodes in wire network, the major differences are which act two different roles meanwhile in Ad Hoc network. In practice, it is not only to research in communication security but also to setup the correct route becomes a very important subject. In this paper, we propose a new secure routing protocol based on IDMAC (Identity-Based Message Access code). According to our analysis, this scheme can prevent the problems of routing forging, modifying, and identity authentication on the Ad-Hoc network. Furthermore, we use NS2 (Network Simulator) to simulate our scheme and discuss how well the efficiency is from the simulation results.