Existing schemes have been firstly analyzed for secure routing protocol in Ad hoc networks. Then we present a new scheme for secure routing protocol base on AODV. Security features in the routing protocol include threshold authentication mechanism based on elliptic curve cryptosystem algorithm and improved the process of authentication without relying on the availability of a certificate authority center. Furthermore, the neighbor supervising mechanism combining with reputation mechanism are adopted to strengthen the management and supervision to network nodes, make the whole process of routing protocol under administration and supervision.