Wireless mobile Ad Hoc network composed by a group of mobile nodes is an emerging network with features of distributed control ,self-organizing and multi-hop. Because of its excellent properties such as high survivability and easy laying,wireless mobile Ad Hoc network gets a lot of attention from researchers in recent years. The original routing protocols cannot meet the requirements of unpredictable existing networks and frequent change of topological,so on basis of previous study,a lot of new AODV routing protocol researches on Ad Hoc network are conducted and this paper gives a proposal of an improved AODV routing protocol based on the adaptive scheme which is called CAODV(cognitive-based AODV). NS2 experimental simulation shows that the CAODV has more excellent properties than AODV,such as less reboot frequency of routing and less controlled load of protocols and higher success rate of repair of broken links,which prove the better adaptive property of CAODV for the dynamically changing wireless Ad Hoc network.