Abstract: Taking into account the effect of the fading channel and multipath disturbance for underwater message communication,we use the chaotic coding method to get the processing gain and apply the correlative signal reconstruction method to utilizing the multipath effect for purpose of reducing code error rate based on the channel estimation using the multi-copy correlation theory.The experimental results show that signal reconstruction method have lower code error rate then signal correlation method.Therefore,chaotic coding mode and signal reconstruction have obvious effect on reducing the multipath disturbance.Generally,some methods of eliminating multipath disturbance are used to reduce the disturbance in underwater communication,but in this paper we creatively utilize the multipath disturbance signal to get the processing gain.The experimental results show that the signal reconstruction method has great significance for underwater message communication.