Abstract: Catalytic pyrolysis of biomass materials was carried out by using a powder particle fluidized bed(PPFB).Three kinds of wood-chips were used in the experiment.Four kinds of catalyst particles were used as bed medium particles and the effect of catalyst on pyrolysis products was investigated.It was found that in the primary pyrolysis of wood, most of the volatile matter was volatilzed at a temperature of 700 K and yields of light aromatic hydrocarbons,i.e., benzene, xylene, toluene and naphthalene(BTXN), increased with an increasing pyrolysis temperature.BTXN yield reached 3.1%(mass),daf at a temperature of 1173 K.When wood-chip was pyrolyzed in a fluidized bed of Zn(3%,mass)/HZSM-5 particles under a hydrogen atmosphere,BTXN yield of 6.1%(mass),daf［BTX:5.5%(mass),daf,N:0.6%(mass),daf］was obtained at 853K.For the ease with the NiMo-A,catalyst the pyrolysis products were almost methane, because its hydrogenation activity is very high.