Biomass fast pyrolysis oil (bio-oil) is considered a promising renewable liquid energy. A feasible upgrading method is co-processing HHDO-oil, which is the heavy fraction of hydrodeoxygenated pyrolysis oil (HDO-oil), with paraffin oil. In this article, kinetic modeling for catalyst deactivation by coke was researched. The results show that the coke is lower by co-processing of HHDO with paraffin oil than other upgrading. Catalyst deactivation is a cascade reaction, the effect of HHDO concentration from 3.18 to 5.08 mol/m3 and the effect of temperature from 753 to 793 K were studied. The kinetic model equation of catalyst deactivation is da/dt = 1.188 x 105 e 18914.85/RT center dot c 0.88 center dot a.