In order to improve the lubrication performance of the stern bearings of marine equipment under low-speed and heavy-loading conditions,the stern bearing of marine propulsion shaft system was chosen as the research object.The lubrication performance parameters of water-lubricated bearings under two-phase flow state was solved by the mixture model of Fluent.The influence of design parameters and environmental factors on bearing lubrication performance was analyzed.Result show that the bearing capacity is positively linearly correlated with the aspect ratio,and as the aspect ratio increases,the growth rate of the maximum water film pressure gradually slows down.The bearing capacity first increases and then decreases with the increase of the number of grooves,with a peak value appearing at 2 grooves.The maximum pressure and bearing capacity of the water film gradually decrease with the increase of groove angle or groove depth,while the friction coefficient increases.The hydrodynamic performance of V-groove bearings is better,with a 7.2% increase in bearing capacity compared to U-groove bearings.The maximum pressure of the water film gradually increases with the increase of the inclination angle γy of the axis around the x axis,and its growth rate gradually increases.When the inclination angle γy is 0.020°,the maximum pressure of the water film is 7.2 times that without axis inclination.The increase in seawater concentration will improve the lubrication performance of bearings,and when the seawater concentration increases from 0 to 100‰,the bearing capacity increases by 15.8%.This study can provide theoretical reference for the design optimization and testing of stern bearings.