In order to enhance the security of Ad Hoc networks,a dynamic trust prediction model was presented in this paper.This model took the account of two factors that affect trust: the node's historical behaviors and capacity of providing services.A time decay function was introduced to estimate the node's direct trust value accurately,and the node's current trust value was assessed by using fuzzy logic rules prediction methods.Finally,this model was applied into AODV routing protocol to verify the validity of the model,which was defined as FTAODV routing protocol,and the two protocol were compared by using NS-2 simulator.The simulation results show that FTAODV routing protocol can effectively detect malicious nodes,thus improving packet delivery ratio,and decreasing average end-to-end delay and routing packet overhead.