Abstract: HCl hydrolysis of Curdlan in dimethyl sulfoxide could massively prepare linear β- 1, 3-glucooligosaccharides. Different kinds of organic solvents were selected to quickly and efficiently separate linear β-1,3-glucooligosaccharides from dimethyl sulfoxide by precipitation and fractional precipitation. Nine kinds of common organic solvents could precipitate Curdlan hydrolysis product,and high feasibility could be got by methylene chloride and ethyl acetate. Methylene chloride and ethyl acetate could be used to separate linear β-1,3-glucooligosaccharides by fractional precipitation and smaller volume but poor selectivity with ethyl acetate. Curdlan concentration,water content and ionic intensity had different influences on fractional precipitation,but degree of hydrolysis had no influence on fractional precipitation. Organic solvent fractional precipitation method could terminate Curdlan hydrolysis reaction and separate hydrolysis product efficiently and quickly. Moreover, it was conducive to recycle dimethyl sulfoxide and organic solvent. Therefore, this method had important guiding significance for separation and purification of β-1,3-glucooligosaccharides.