Abstract: Based on the Computational Fluid Dynamics (CFD) method, numerical simulation computation on the flow field of inclined plate separator was carried out with the standard k-ε and RNG k-ε models via ANSYS-CFX software, and the distribution rule of the speed vector for the interior flow field of separator and the distribution rule of gas concentration as well as the rule of liquid track under two turbulence models was obtained. Comparative analysis of the two turbulent flow models indicated that when liquid was distorted sharply in flowing, additional generator monomials added to ε equation of the RNG k-ε model would increase rapidly, which improved the ability in forecasting the complex turbulent flows as rotational flow and buoyant flow. Compared with the standard k-ε model, the RNG k-ε could more reasonably simulate the flow field distribution for the inclined plate separator.