The present invention relates to the use of an extract of Boehmeria nivea for treating liver cancer. The herb Boehmeria nivea was extracted by Acetone first. Then the liquid-liquid extraction method was used step by step with solvents (n-hexane, ethyl ester, n-butanol) to obtain herbal extracting liquids. And the herbal extracting liquids were condensed to obtain the herbal extracts separately. The herbs extracts were estimated their anticancer activities by HEPG2 Cell line. Each extract was demonstrated its effect of decreasing proliferation of the liver cancer.本發明係關於一種蕁麻科(Urticaceae)植物,係苧麻(Boehmeria)含具抗肝癌活性物質。將苧麻先以丙酮萃取後,再分別以正己烷、乙酸乙酯、正丁醇進行液-液溶劑萃取法區分出不同萃取液,該等萃取液經抗肝癌活性(HEPG2)評估後,即為各具抗肝癌活性之活性區分層;彼等所得萃取區分層具抗活性物質對於肝癌細胞具有抑制、或毒殺效果。