This study was performed to investigate the effect of Bunsimgieum on antitumor effect after sarcoma-180 cells transplantation into peritoneal cavity or left groin and immune responses on the depressed immunity induced by methotrexate in mice. The Bunsimgieum extract of 10mg/kg was orally administered 14 days for antitumor effects and 21 days for immune responses. 50% inhibitory concentration($IC_{50}$) of SUN-1, SUN-C4, and SUN-396 cancer cell, mean sunvival days and body weight of tumor bearing mice, and growth of tumor mass for antitumor effect; delayed type hypersentivity, hemagglutinin titer, hemolysis titer, rosette forming cells, natured killer cell activity, lymphocyte transformation, productivity of interleukin-2, and phagocytic activity for their immune responses were measured in ICR mice. Significance in antitumor effect is noted in the enlongation of mean life days and inhibition of tumor growth(p<0.01, respectively). Significance of immune responses is also noted in hemolysis titer, lymphocyte transfumotion, IL-2 productivity, phagocytic activity, and natural killer cell activity at E/T ratio 100:1(p<0.01, respectively). Significant in rosette cell formation was seen at dosage of 20mg/kg(p<0.01). However, Difference of body weight as antitumor effect, delayed type hypersensitivity, and hemagglutinin titer were not shown significantly. According to the above results, it could be suggested that Bunsimgieum has prominent antitumor and immunity enhancing effect.