Artemisia capillaris THUNB is a perennial herb that belongs to the family Compositae spp and the most common plant among the various herbal folk remedies used in treatment of abdominal pain, hepatitis, chronic liver disease, jaundice and coughing in Korea. This experiment was conducted to investigate cytotoxic effects of Artemisia capillaris extracts on the Hepa-1c1c7 and Sarcoma 180 cancer cells on in vitro experimental tests. On in vitro tests using MTT assay and SRB assay, the extracts showed prominent cytotoxic effects on the two kinds of cancer cell lines, respectively. Antihumor effects appeared in the concentration of over $250{mu}g/mL$ of both ethanol and ethyl acetate extract, over $500{mu}g/mL$ of methanol extract, over $5000{mu}g/mL$ in water extract and over 50% cytotoxicity on the Hepa-1c1c7 and Sarcoma 180. The results suggest that Artemisia capillaris extracts have prominent cyotoxic effects on the cancer cell lines Hepa-1c1c7 and Sarcoma 180.