Background and purpose: Oxymatrine, which is the main effective component of Sopkora flavescens Ait, has anti-fibrosis and antiviral activities, and also has a good effect on leukopenia after either chemotherapy or radiotherapy. Recent studies showed that oxymatrine has the abilities of anti-invasion and killing tumor cells in some degree, and as a supplementary anticancer drug in chemical therapy. In this study, we investigated the antitumor mechanism of oxymatrine by observing cell proliferation and VEGF expression in human gastric cancer SGC-7901 cell line. Methods: Human gastric cancer SGC-7901 cells was cultured in vitro and treated with oxymatrine, then cell proliferation was examined by the method of MTT. Immunohistochemistry was applied to examine the protein expression of VEGE The transcriptions of VEGF mRNA were demonstrated by RT-PCR technique.Results: Low-dose (0.5 mg/mL) oxymatrine has a mild inhibitory effect on cellular proliferation of SGC-7901 cells (P>0.05). When concentration exceeded 1 mg/mL, oxymatrine significantly inhibited cellular proliferation in a time-and concentration-dependent manner, and down-regulated the mRNA and protein expression of VEGF (P<0.05).Conclusion: Within a certain drug concentration, oxymatrine can inhibit the proliferation of SGC-7901 cells and play a potential role in inhibiting angiogenesis by down-regulating the expression of VEGF.