Objectives: To elucidate the antitumor activities of Hang-Am-Dan (HAD), we investigated the anti-proliferative effects and related mechanisms of HAD, the main ingredients such as Cordyceps Militaris and Santisigu Tuber, and its main effective components cordycepin and colchicin, respectively. Methods: We cultivated Calu6 and MCF-7 cells and gave them phosphate-buffered saline extracts of HAD, each ingredient of HAD, and the main effective components of each ingredient. After these processes, we performed MTT assay, BrdU assay, TUNEL assay, SDS-PAGE and Western blot analysis and observed the results. Results: The survival rate of these two cancer cells in HAD were 34-38%. The survival rate in extract of Cordyceps militaris (ECM) and extract of Santisigu tuber (EST) were both about 50%. Cordycepin showed decreased survival rate in both cancer cells, 32% and 89%. Colchicin also showed decreased survival rate, 30% and 16%. We observed that all of the cancer cells got apoptotic bodies after adding the extracts and they have more apoptotic bodies when they were exposed to more extracts. The expression of caspase-3 was increased in Calu6 cell lines treated with the ECM, cordycepin and colchicin. The expression of p53 and p21 were increased in the MCF-7 cell lines treated with the ECM and cordycepin. Conclusions: HAD showed cytotoxic activities on the two kinds of human cancer cell lines, Calu6 and MCF-7. Additionally, HAD and its main ingredients caused a dose-dependent inhibition of cell proliferation and induced the apoptotic cell death.