Abstract: The propeller loads that the propulsion shaft system endures during the ship's maneuvering directly affect the service life of the shaft system and the operational safety of the ship. However, due to the complexity of loads in actual navigation, existing methods struggle to accurately calculate the response law of the shafting under such working conditions. In this paper, a method combining the improved discrete four-degree-of-freedom MMG ship maneuvering model with computational fluid dynamics (CFD) is employed to conduct a numerical simulation study on the response characteristics of the marine propulsion shafting during turning navigation. The research indicates that during turning navigation, the turning radius decreases continuously with an increase in rudder angle; the lateral and axial thrusts of the propeller vary significantly with changes in rudder angle and rotation speed; and the combined action of propeller hydrodynamic force and rotational centrifugal force results in the asymmetric distribution of loads on the shaft, which requires special attention during the production, assembly, and navigation steering of the shafting. This study can provide a theoretical reference for the design optimization of large ship propulsion shafting and the improvement of navigation control.