Abstract: Cooperation transmission can combat signal fading caused by multipath propagation in wireless networks,and consequently achieve spatial diversity gains.For wireless relay network with unicast transmission,a novel cooperation scheme based on physical-layer network coding is proposed in this paper.Theoretic analysis shows that,compared with traditional cooperation transmission scheme and the cooperation scheme based on straightforward network coding,this cooperation scheme can decrease transmission slots efficiently,and obtain higher network throughput.Furthermore,its symbol error probability performance is simulated for different SNR values.