Abstract: To study the machining of marine propeller, a method of grinding the propeller with electroplated diamond belt was proposed, and the process factors, which had effects on surface roughness of the propeller, were analyzed by experiments. The effects of grinding pressure, belt linear velocity, and grinding feed speed on surface roughness were studied through a single factor experiment, and the optimal combination of the parameters was obtained, namely grinding pressure 15 N, belt linear velocity 30 m/s, and grinding feed speed 20 mm/s. It is also found that both zirconium corundum abrasive belt and diamond abrasive belt have basically the same rules for the surface roughness of the propeller under various process parameters, while the diamond abrasive belt has a better life than the zirconium corundum belt does under the same grinding parameters, with an increase of 125%.