Abstract: The fraction of water-soluble lignin-carbohydrate complexes (LCC) containing sodium salt and low molecular weight (Mr) substances (Mr substances in the LCC. The results indicate that sodium salts and low Mr substances can be removed effectively after a total of ten times ultrafiltration loops with pressure 0.10MPa and concentration 0.5% were performed. The LCC fraction, which consists of 95.5% carbohydrate and 1.5% lignin, was obtained with high yield and purity.