Objective To investigate the relationship between HGF/c-Met and biological behavior and prognosis of gastric carcinoma.Methods The expression of HGF.c-Met.microvessel density and microlymphatic densitv in 58 cases of gastric carcinoma and 27 cases of gastric ulcer were evaluated by immunohistochemistry，using monoclonal antibodies for HGF，c-Met，CD34 and Lyve-1 respectively.Results HGF and c-Met protein were overexpressed in gastric carcinoma，and were significantly higher than those in the mucosa of gastric ulcer(P＜0.01).The microvessel density and microlymphatic density of gastric carcinoma were significantlv different between those with and those without lymphatic metastasis and distant metastasis(all P＜0.05)：The positive expression of HGF and c-Met in those with lymph node metastasis(86％，80％)was significantly higher than those without lymph node metastasis(57％，36％)，P＜0.05.That with distant metastasis(100％.94％)was higher than that without(71％，60％)，P＜0.01.The 5 year survival rate in patients with positive HGF and c-Met expression was much lower than that with negative expression(P=0.019，P＜0.01)，Multivariate analysis indicated HGF and c-Met expression，depth of invasion.lymph node metastasis.distant metastasis，microvessel density and microlymphatic density were all independent prognostic factors of gastric carcinoma.ConclusionsExpression of HGF and c-Met closely correlated with carcinogenesis，development and prognosis of gastric carcinoma.