Kitchen garbage and dewatered sewage sludge were thermochemically liquidized at 175 degrees C and 4 MPa with 1 h of holding time. The liquidized garbage and sludge were separated into liquid and solid fractions, respectively. The diluted liquid fraction of the liquidized garbage and sewage sludge were continuously anaerobically digested using upflow anaerobic sludge blanket method, The digestion ratio of the liquid fraction separated from the liquidized garbage was 74-75% at the added TOC concentration of 17.0 g.l(-1) and the TOC loading rate of 1.8-2.8 mg.cm(-1)-granule.day(-1). The digestion ratio in the liquid fraction separated from the liquidized sewage sludge was 57-75% at the added TOC concentration of 7.9 g.l(-1) and the TOC lending rate of 2.2 mg.cm(-1)-granule.day(-1). The solid fraction could be processed to refuse derived fuel according to its decreased moisture content. The energy balances of this treatment process for kitchen garbage and sewage sludge: were initially analyzed to be better than those of direct incineration.