An intelligent lubricating system for a marine engine is composed of a temperature sensor (1), a liquid level meter (2), a flow meter (3), a pressure sensor (4), an in-oil-particle detector (5), an in-oil-moisture detector (6), a data acquisition and processing unit (7), an alertor (8), an automatic oil purifier (9) and an upper computer (10), wherein the temperature sensor (1), the liquid level meter (2), the flow meter (3), the pressure sensor (4), the in-oil-particle detector (5), the in-oil-moisture detector (6), the data acquisition and processing unit (7), the alertor (8), the automatic oil purifier (9) and the upper computer (10) are connected through wires. The temperature sensor (1) and the liquid level meter (2) are arranged in an oil tank (21), the flow meter (3) and the pressure sensor (4) are arranged on oil pipelines of lubrication points of the marine engine, the in-oil-particle detector (5) and the in-oil-moisture detector (6) are arranged outside the oil tank (21) and are connected with the oil tank (21) through pipes, and the upper computer (10) is arranged in an operation room and is communicated with the data acquisition and processing unit (7) in a wired or wireless mode. According to the intelligent lubricating system for the marine engine, the on-line detection technology and the automatic maintenance technology are applied to carry out improvement on the lubrication system on the marine engine, the lubrication problems in the marine industry can be solved to a great extent, and huge benefit can be obtained on energy saving, emission reduction and noise reduction.