R290 has been considered for use in air-conditioning systems as a low global warming potential (GWP) refrigerant. This paper describes the tribological characteristic of the vane-piston tribopair in a R290 rotary compressor. For the purpose of simulating the tribopair working conditions,the vanes and rolling pistons of a compressor were directly adopted as test specimens. All of the tribological tests were performed under sealed high-pressure conditions,with test conditions such as the relative sliding speed,loads,and temperatures set based on actual operating conditions of a compressor,and the friction coefficients,scuffing resistances,and wear depths were measured. Furthermore, the morphological changes were investigated using a scanning electron microscope after the tests. As a comparison benchmark, tests were also conducted using R410A/polyolester oil. From these tests,it was evident that the friction coefficients and scuffing load of the vane-piston interface in the presence of R290 /mineral oil were respectively 0.05 - 0.10 and 300 N higher than those of R410A/polyolester. On the other hand,the wear resistance ability with R290 /mineral oil was better than that with R410A/polyolester.