Objective To study the proliferative inhibition and apoptosis promoting activity of oxymatrine on human lung cancer cells (A549) and human hepatocellular carcinoma cells (HepG-2) in vitro,and make a comparison.Methods Effect of oxymatrine on the proliferation activity of two kinds of tumor cells were compared by MTT method and growth curve method.HE staining,Hoechst 33258 fluorescent staining and transmission electron microscopy were used to compare morphological changes.Results MTr results showed that,compared with control group,the survival rate of oxymatrine 200,400,and 800 μg/mL concentration group in A549 and HepG-2 cells decreased significantly (P ＜ 0.05,0.01),half inhibitory concentration (IC50) were 1055.45 and 774.11 g/mL respectively;The growth curve showed that,compared with control group,the number of cells in oxymatrine group of HepG-2 cells cultured for fourth and fifth day and A549 cells cultured for fifth day decreased significantly (P ＜ 0.05,0.01).Oxymatrine affected morphological changes of HepG-2 cells more significantly than A549 cells.The number of cells in the oxymatrine group was significantly reduced;And the cell villi was decreased,the nucleus was small and round,and the cell apoptosis morphological characteristics were obvious.Conclusion Oxymatrine can inhibit the proliferation cells and promote the apoptosis of tumor cells.It affected HepG-2 cells more obviously,which suggests that it may have different sensitivity to different tumor cells.