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The effects of aerobic composting pretreatment on the mixed material of pine sawdust (6.35mm,9.53mm,12.70mm) and food wastes and the influence on subsequent dry anaerobic digestion were studied by adding the food wastes aiming at the problems of the less effects and the high costs of pretreatment of conifer pine before anaerobic digestion. The experimental results showed that the pretreatment effects of aerobic composting process on the pine sawdust were obvious. But the pretreatment effects decreased with the increase of particle size of pine sawdust. The biogas production rates of anaerobic digestion of the raw materials, which were pretreated by aerobic composting, were all within the ranges of 199~215L/kg, about 140% of unpretreated samples. And the total volatile fatty acid of the material, which had more subsequent potential for generating biogas, were all 24.5 or so after anaerobic digestion, about 150% of unpretreated samples.