In this study, nano-sized tungsten carbide (2.8 nm) particles with enhanced properties were successfully synthesized using removable ceramic coating method and then applied as dispersed catalysts to hydrocracking of vacuum residue, which was carried out at 673 K for 4 h with initial hydrogen pressure of 70 bar. The nano-sized particles were then characterized with XRD, TEM, and BET analysis. The temperature programmed desorption analysis results showed that nano-sized tungsten particles are capable of superior hydrogen adsorption (compared to bulk tungsten carbide) as well as high catalytic performance not only in commercial liquid yield (Naphtha, middle distillate, and gas oil; 46.7 wt%) but also in coke formation (5.9 wt%). Finally, the characterization and performance correlation of the nano-sized tungsten carbide catalyst were analyzed.