Abstract: The properties of the oil obtained by co-pyrolyzing a mixture of rice husk biomass and waste tire in a tubular fixed-bed with MCM-41 and SBA-15 as catalysts were investigated with gas chromatography, elemental analyzer, viscometer and calorimeter.The results showed that the yield and heating value of the pyrolytic oil increased and its viscosity and density decreased as the percent of waste tire in the mixture was increased.Through pyrolyzing the mixture with rice husk accounting for 60%(mass), the liquid yield and heating value of the pyrolytic oil reached 44.5%(mass) and 40 MJ·kg-1 (approaching that of diesel)respectively.The temperature could obviously affect the yield of the pyrolytic oil and limonene content in the oil,both of which reached a maximum at 500℃.The limonene content was lower than that of the weighted value obtained through individual pyrolysis and the oxygen content was higher than that of the weighted value through individual pyrolysis.Through co-pyrolyzing the mixture of rice husk and waste tire, it was found that synergetic effect and interaction might take place for some components.Catalysts such as MCM-41 and SBA-15 greatly reduce the viscosity and density of the oil.Comparing with MCM-41, SBA-15 showed better catalytic effect than MCM-41. Comparing with the diesel(0#), the viscosity and density of the pyrolytic oil were slightly higher than those of diesel.