Characteristics of elemental fluorine and carbon-fluorine bonds were analyzed. The barrier and oil-resistance properties of direct fluorination of HDOE were unveiled from molecule structure. The HDPE surface fluorination results in the increase of surface energy, cross link to some extent and shrinkage of polymer free volume.The application of direct fluorination of HDPE in oil in oil ＆ gas storage and transportation fields were reviewed, including oil and gas pipe,plastic petrol-tanks and HDPE impermeable membrane applied in oil tank foundation. After direct fluorination processing, the anti-corrosion and the permeability to hydrocarbons of HDPE pipes are strengthened. With the development of technology, it will be the trend that the multi-layer fuel tanks replace the single layer fuel tanks. The HDPE is applied as the outermost layer of multi-layer structure to ensure the processing property and the impact resistance in low temperature.