Abstract: This paper studies the system outage performance of a energy harvesting based two way relay network (TWRN) considering transceiver hardware impairments (HIs), where the terminals process the signals from direct and relaying links via the selection combining (SC) and maximum ratio combining (MRC) schemes respectively. The system outage probability under the SC scheme is derived. Based on the expression, the paper identifies two crucial effects on the system outage performance caused by HIs, i.e., relay cooperation effect and system cooperation effect. Furthermore, the paper obtains the expression for the system outage probability under the SC scheme. Finally, computer simulations are provided to study the effects of various system parameters on the system outage performance, and compare the performance gaps between the SC and MRC schemes. The simulation results are as follows. The TWRN with the MRC scheme only occurs system cooperation effect caused HIs; The SC scheme is more sensitive to HIs than the MRC scheme; When the data rate is smaller than system cooperation thresholds, the MRC scheme can achieve higher system outage probability than the SC scheme.