The utility model relates to a quantitative loading system, including product tank and tank wagon, this system still includes loading control computer, is connected with the control unit I, IC -card card reader and document printer on the loading control computer respectively, be equipped with the control unit II, regulating unit, the control unit III, mass flow meter unit and oil filling riser between product tank and the tank wagon in proper order, the control unit I is connected with the control unit II and the control unit III respectively, the tank wagon is connected with electrostatic grounding device, the control unit I and electrostatic grounding device are connected, regulating unit be two parallelly connected governing valves, the mass flow meter unit be two parallelly connected mass flow meter, be equipped with the bypass on the pipeline between regulating unit and the the control unit III, be equipped with portable calibration flowmeter in the bypass. This system not only can realize automatic quantitative loading, but also has guaranteed the accuracy and the stability of measurement, has improved work efficiency.