Abstract: To improve the energy efficiency of R290 natural refrigerant heat pump systems and investigate the influence of dual-pressure condensation configuration on system performance, an experimental test bench for R290 dual-pressure condensation heat pump was built in this study. Taking the single-pressure condensation system as the control group, the overall system performance was tested, and exergy loss of key components was analyzed. The results indicate that the COP of dual-pressure condensation system is higher than that of single-pressure condensation system, with a relative enhancement rate ranging from 9.60% to 29.82%, and the performance improvement becomes more prominent with the increase of outlet water temperature and evaporation temperature. The dual-pressure condensation system can reduce the exergy loss per unit heating capacity of the system, with a reduction of 11.11% to 18.60% compared with that of the single-pressure condensation system. The exergy loss per unit heating capacity of the compressor, condenser and throttling valve in the dual-pressure condensation system are all lower than those of the single-pressure condensation system, among which the condenser exergy loss is decreased by 12.96%.It demonstrates that the dual-pressure condensation system can effectively improve the energy efficiency and reduce irreversible losses of R290 heat pump system, which can provide experimental basis for the performance optimization and engineering application of natural refrigerant heat pump system.