Abstract: Oil-sorbing material was prepared from intermediate cutting wood of Chinese fir by processes comprised of wood cooking,mechanical fibrillating and thermo-degradation.Relations between oil-sorption properties of the product and temperature,extract content were studied.Water sorption of heat-treated fiber decreased when temperature increased.Oil-sorption(except at 350℃) showed much the same pattern,but the selectivity for oil was increased.Hot water and 1% NaOH extracts decreased with increasing temperature.Ethanol-benzene extracts decreased at 200-250℃ and then increased at 300℃.Significant decreases of ethanol-benzene extracts occurred at 400℃,which were caused by (secondary) decomposition and volatilization of these products.These results indicate that oil selectivity of the heat-(treated) wood fiber depends on the increased hydrophobicity of polysaccharides and decreased hydrophilic components.The adhesion of lipophilic pyrolyzate on the fiber surface greatly affects oil selectivity.