In the previous study we described the antitumor effect of GLB, a protein-polysaccharide fraction separated from the growing tips of Ganoderma lucidum, against sarcoma 18 0 solid tumor in ICR mice. In this study, we separated an acidic protein-polysaccharide fraction, GLB-A, and a basic protein-polyaccharide fraction, GLB-B, from GLB by differential precipitation, and elucidated their antitumor and immunomodulatory activities. When ip injected at the dose of 50mg/kg/day into the ICR mice, GLB-A and GLB-B inhibited the growth of ip implantated sarcoma 180 cells by 32.4% and 21.0%, respectively. Of these, GLB-A increased the % lymphoblast in the spleen of the tumor-bearing and the normal mice by 20.9% and 123.0%, and the CD4/CD8 ratio by 73.3% and 22.4%, respectively. GLB-A also increased the expression of CD25 (IL-2 receptor alpha ch0ain) in normal mice by 82.0%. These results strongly suggest that GLB-A is a promising candidate for antitumor immunomodulatory medicine.