Objectives : The object of this study was to observe anticancer and related immunomodulatory effects of Insamyangyoung-tang extracts (ISYYTe) on non-small cell lung carcinoma (squamous epithelial carcinoma), NCI-H520, xenograft Balb/c nu-nu nude mice. Methods : Three different dosages of ISYYTe, 50, 100 and 200 mg/kg were orally administered once a day for 42 days from 11 days after tumor cell inoculation. Six groups, which are intact control, tumor bearing control, 5-fluorouracil (FU) 30 mg/kg, ISYYTe 50 mg/kg, ISYYTe 100 mg/kg, ISYYTe 200 mg/kg, each of 8 mice per group were used in the present study. Changes on the body weight, tumor volume and weight, lymphatic organ (spleen and popliteal lymph node), serum interferon (IFN)-${gamma}$ levels, splenocytes NK cell activity and peritoneal macrophage activities, splenic tumor necrosis factor (TNF)-${alpha}$, interleukin (IL)-$1{eta}$ and IL-10 contents were observed with tumor mass and lymphatic organ histopathology to detect anticancer and immunomodulatory effects. Results : As results of ISYYTe 50, 100 and 200 mg/kg treatment, decreases in the tumor volumes and weights were detected. At histopathological observations, decreases of tumor cell volumes in tumor masses were dose-dependently decreased mediated by increases of apoptosis among tumor cells by treatment of all three different dosages of ISYYTe. As results of tumor cell inoculation, marked decreases of spleen and popliteal lymph node weights, serum IFN-${gamma}$, splenic TNF-${alpha}$, IL-$1{eta}$ and IL-10 contents and splenocytes were observed with histopathological atrophic changes of spleen and popliteal lymph nodes. Conclusions : Over 50 mg/kg of ISYYTe showed favorable anticancer effects on the NCI-H520 cell xenograft with immunomodulatory effects. Although relatively lower anticancer effects were observed in ISYYTe 200 mg/kg treated mice as compared with 5-FU 30 mg/kg treated mice, there are no meaningful favorable immunomodulatory effects were observed after 5-FU treatment in the present study.