Abstract: Ni-W hydrocracking catalysts were prepared by co-impregnation method on the carrier consisted of ZSM-5, USY zeolites and Al2O3 using ammonium metatungstate and phosphotungstic acid as tungsten source, respectively and then modified by phosphorus. The catalysts were characterized by BET, NH3-TPD, Py-IR, XRD, XPS and HRTEM techniques. The hydrocracking performance of the catalysts was evaluated in a fixed-bed reactor, using a hydrotreated diesel fraction obtained from middle/low-temperature coal coking process. The catalyst using phosphotungstic acid as tungsten source exhibits a higher sulfidation degree of W and Ni, resulting in higher hydrocracking activity. The total aromatics contents in the hydrocracked products are decreased by 7.06% and the total saturated hydrocarbon contents are increased by 6.70%, compared with the catalyst using ammonium metatungstate as tungsten source. The addition of phosphorus increases the strength of weak and moderate strong acid, improves the B acid ratio and the sulfidation level of W and Ni of the catalyst prepared using ammonium tungstate as tungsten source, thus enhances its hydrocracking activity. On the P modified catalyst, the total aromatics content in the hydrocracked products was decreased by 7.90% and the total saturated hydrocarbon contents are increased by 7.54%.