The invention relates to an oil consumption detection system, aiming at solving the problems of poor engine oil consumption detection precision and high cost. The invention provides an engine oil consumption detection system which comprises an engine, a fuel tank, a controller and a fuel level sensor, wherein the controller determines an instant fuel consumption of the engine in a preset time interval according to a change value of a liquid level in the fuel tank detected by the fuel level sensor in the preset time interval and by combining a corresponding relation between a cross section of the fuel tank and a height of a fuel liquid level, and establishes a mapping relationship between a real-time oil consumption and time. The engine oil consumption detection system adopts the fuel levelsensor, so that the engine oil consumption detection system is low in cost, high in automation degree and high in precision, and can be used for a real-time oil consumption monitoring in a whole lifecycle of all excavators. The engine oil consumption detection system provides big data for intelligence and product technology upgrading of the excavators and provides a money-saving strategy for customers.