Abstract: In order to meet the requirements of producing phase V national standard diesel, part of FH-40C hydrotreating catalyst in Huizhou Refining & Petrochemicals Co. coker gasoline/diesel hydrotreating unit was replaced with a new generation of diesel deep hydrodesulphurization catalyst FHUDS-6 developed by SINOPEC Fushun Research Institute of Petroleum and Petrochemicals. The calibration was carried out at 110% load (269 t/h), and the results show that the catalyst combination of FH-40C/FHUDS-6 can produce refined diesel (the average sulfur content of 5.2 μg/g, the cetane number of 54.57 with a mixed feed of coker gasoline/diesel and straight run diesel (the average sulfur content of 1 923 μg/g at reaction conditions of 7.7 MPa in cold high pressure separator, average temperature of 365 ℃, LHSV of 1.931 h-1 and the ratio of hydrogen to oil of 523. The desulfurization rate reaches 99.786%, indicating the excellent performance in deep hydrodesulphurization and cetane number improvement of FHUDS-6 catalyst. The quality of refined diesel can meet the requirements of national phase V standard for diesel product.