Objective To observe the antitumor activities of different solution extracts of Plumbago zeylanica L.in vitro.Method MTT method was used to detect the inhibitory effects on four kinds of cancer cells.Results chloroform extracts had significant in- hibitory effects on the breast cancer cell(Bre-04),the nerve cancer cell(N-04)and the lung cancer cell(Lu-04),IC_(50) were 0.2699mg/ml and 0.2634mg/ml,0.4961mg/ml respectively.IC_(50) of chloroform extract on the HepG2 was 0.9379mg/ml. IC_(50) of petroleum ether e...