Due to the variability of the underwater environment, individual nodes in the underwater wireless optical communication sensor network cannot meet the requirements of line-of-sight transmission. In order to restore effective communication between nodes, this paper proposes a relay routing algorithm based on relay cooperative transmission method, and the bit error rate of the mixture exponential-generalized Gamma model is used as the relay selection metric. In order to ensure that the selected relay node can solve the link failure problem in the sensor network under the condition of low energy. In terms of relay selection, consider the power threshold when the node communicates successfully. The simulation results show that the relay cooperative routing algorithm for reconstructing the transmission link can guarantee low bit error rate and maximize the network lifecycle simultaneously.