Abstract: In order to optimize the energy efficiency of the two-way single-relay full-duplex system， simultaneous wireless information and power transfer technology was introduced at the relay node， and a two-way simultaneous wireless information and power transfer full-duplex relay system was proposed. The energy was collected by the relay node of the system in a power split mode， and the collected energy was used for decode-and-forward.Under the guarantee of the user's service quality requirements， the energy efficiency optimization problem was transformed into an optimization problem with minimum energy consumption. According to the transmission time slot and the channel capacity requirements of each time slot， it was further divided into two sub-optimization problems.Then， with the goal of maximizing energy efficiency， the transmission power was calculated according to the channel capacity of each time slot， and the transmission time and power split factor were calculated using the decode- and-forward characteristics， thus the energy efficiency optimal solution was obtained.Simulation shows that the energy efficiency of the proposed two-way simultaneous wireless information and power transfer full-duplex relay system is 1.3 times that of the one-way simultaneous wireless information and power transfer full-duplex system， 2 times that of the two-way full-duplex amplify-and-forward relay system and 2.6 times that of the two-way full-duplex decode-and-forward relay system.