Abstract: The liquefaction of bagasse was studied in order to explore a new way for its use.The conditions of bagasse liquefaction,such as liquefaction solvent,liquid solid ratio,reaction temperature were investigated while the sulfuric acid as a catalyst.It indicated that the liquefaction efficiency of 96 could be reached in PEG #400,and the lignin was liquefied completely.The liquefied product is a polyether ester polyol and its hydroxyl value is 160mg KOH/g~300mg KOH/g,which means that the product can be satisfied as a material for moderate intensity polyurethane foam.