Abstract: Two simulative oil tanks are provided in the test, one of which has a layer of fluorinated polyethylene microspheres on the gasoline surface, and the other of which is an empty tank for comparison with gasoline treatment free. Gas chromatography technology is adopted for the online detection analysis of the light gas evaporation loss of the two simulative oil tanks, with the change trend of the oil and gas content in the two simulative oil tanks at room temperature and controlled temperature obtained. The result indicates that compared with the empty oil tank for comparison, the oil tank with a layer of fluorinated polyethylene microspheres on the gasoline surface shows a noticeable decrease in its light gas evaporation loss. Based on the time required by the light gas in the simulative tank with fluorinated polyethylene microspheres to reach saturation state, the calculated effectiveness of fluorinated polyethylene microspheres inhibiting evaporation loss at the controlled temperature is 71%. The principle is that fluorinated polyethylene microspheres can not only prevent light gas from transferring heat to the oil to lower oil surface temperature, but also reduce the evaporation surface area of the oil, thereby further inhibiting the evaporation of the oil.