An increasing attention has been paid to the portential used of lignocellulosic materials for chemicals, toods and fuels production. The most reasonable way to find economic utilization of biomass is the production of chemicals. The waste liquor of pulp mills contains large quarvtity of lignin and hemlcellulose. These materials from conventional pulping mills are not suitable for their appropriate utilization, because they are not only greatly degenerated but also very difficult to be separated each component. It is necessary to develop a new pulping process in order to overcome above difficulty. The solvolysis of wood with cresol and water mixture gives pulps of good quality. Furthermore the reaction mixture can be separated easily into water and organic layer after cooking. The water layer mainly contains sugary from hemicellulose and the organic layer contains lignin. The separation of wood residues can be carried out effectively by the cresol and water mixture. The objectives of this work were, (i) to find the most effective sotvolyais conditions and method for the delignification of wood, (ii) to find out the changes of carbohydrate and property of wood resicues and water solubles under the various acids catalysed sololysis cooking Pine(Pinus dnesiflora) and oak(Quercus variablilis) wood chips were delignified with cresol and water mixture containing various acids as a catalysts at 180℃∼200℃ for 60∼150 minutes. The results of this work were as follows : Delignification of wood meals by solvolysis cooking with cresol and water mixture at higher cooking temperature, the rates of delignification increased, depends critically on the cooking temperature rather than cooking time. At 180℃ temperature, however, the purity of cellulose was increased with increasing cooking time. The ratio of monosaccharide to oligosaccharide in water layer after cooking increased with increasing cooking time at lower temperature, but it was decreased at higher temperature. Water solubles were mainly composed of oligosaccharide. As temperature and time of cooking increased, the degradation of cellulose was increased. The ratio of cresol and water was an important factor for delignification and degradation of carbohydrate. As charge of cresol increased, the degradation of carbohydrate decreased, but as charge of water in creased, take mainly place more degradation of carbohydrates than delig-nification. Addition of 1.0% formic acid as a catalyst, not only delignification of wood meals accelated but also degradation of carbohydrates, especially monosaccharide content in water solubles decreased. Addition of 0.1% citric acid as a catalyst, delignification of pine chips at 180℃ cooking temperature were accelated. At high cooking temperature, delignification was decreased and degradation of carbohydrate were take placed. In the case of oxalic acid addition as a catalyst, the most effective a proper condition for separation of pine wood components were identified to be 0.1%, 190℃, 60 minutes. Delignification of pine chips depends upon more closely with temperature than concentration of oxalic acid. Degradation of carbohydrate increased, compared with none catalyst. Compared with the results obtained from other acid catalysts, addition of acetic acid gave negativel effect on delignification. Addition of 0.05% and 0.1% phosphoric acid as a inorganic acid catalyst in stead of organic acid catalysts, the rates of delignification and degradation of carbohydrate of pine chips were increased with concentration of phosphoric acid. In the case of more than 1.0% Phosphoric acid addition, pine chips took place more degradation of carbohydrate than celignification. Addition of organic and inorganic acid as a catalyst, degradation of carbohydrate were increased. The mild condition of lower concentration and Lower temperature showed effect of catalyst, but took place degradation of carbohydrate at higher temperature and acid concentration. The add