Abstract: The turning quality is a crucial measure of ships' maneuverability，and the numerical prediction of hydrodynamic force and moments on ships is indispensable for the true understanding of ship's turning motion. Based on the computational fluid dynamics（CFD）method，this paper develops a numerical solution of the incompressible RANS equation in a steady rotating coordinate system for the purpose of hydrodynamic force prediction. To simulate the turning motion，a body-force propeller model is adopted instead of the real propeller. A comparison between the calculated results and theoretical values shows fair agreement，and the deviation is seen to be uncorrelated with the body-force propeller model. Thus，the proposed method is suitable in analyzing the hydrodynamic performance of ships in turning motion.