Abstract: A series of NiW hydrocracking catalysts with different contents of USY with high silica to alumina ratio (Si/Al=42) were prepared by co-impregnation method. The catalysts were characterized by NH3-TPD, BET, XRD, XPS and HRTEM techniques. The hydrocracking performance of the catalysts was evaluated in a fixed-bed reactor using diesel fraction from the hydrotreated middle/low-temperature coal tar. The results show that the NiW catalysts containing USY zeolite have a high hydrocracking activity and the cracking activity is mainly derived from the acidity of USY zeolite. Under the preconditions of ≥95% of the product yield, and the catalyst having appropriate USY zeolite content (30%), the density of the product decreases to 0.8485 g/ml from original 0.8990 g/ml, or less from original 17.4%, the C/H mole ratio decrease to 6.89 from original 7.32, the 50% distillation temperature decrease to 270℃ from original 304℃ and the cetane index increases to 43.5 from original 40.0, and the polycyclic aromatic hydrocarbons are cracked almost completely.