Objectives : This study was to observe anticancer and related immunomodulatory effects of Kwibi-tang extracts (KBTe) on non-small cell lung carcinoma (squamous epithelial carcinoma), NCI-H520, xenograft Balb/c nu-nu nude mice. Methods : Three different dosages of KBTe, 50, 100 and 200 mg/kg were orally administered once a day for 42 days from 11 days after tumor cell inoculation. Six groups, each of 8 mice per group were used in the present study. Changes in body weight, tumor volume and weight, lymphatic organs (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. The results were compared with a potent cytotoxic anticancer agent, 5-FU (5-Fluorouracil) 30 mg/kg, intraperitoneal treatment (3-day intervals for 42 days, the optimal effective treatment regimes already confirmed). Results & Conclusions : This study suggest that over 50 mg/kg of KBTe showed favorable anticancer effects on the NCI-H520 cell xenograft with immunomodulatory effects. Although relatively lower anticancer effects were observed in KBTe 200 mg/kg treated mice as compared with 5-FU 30 mg/kg treated mice, no meaningful favorable immunomodulatory effects were observed after 5-FU treatment in the present study.