Abstract: Based on computational fluid dynamics (CFD) method and dynamics mesh technology, the numerical simulation of rolling piston compressor was performed. Main factors affecting the volumetric efficiency were studied by comparing the theoretical calculation and experimental data. The result shows that the volumetric coefficient and the temperature coefficient agree well with theoretical expectations. The pressure coefficient depends directly on the suction chamber pressure fluctuations which were caused by the inlet channel flow resistance, and the leakage coefficient is the main factor affecting the volumetric efficiency. The results imply that the method can effectively identify the influence of various factors on the volumetric efficiency, explain their roles in the working process, and be practical in engineering application.