ObjectiveTo study the expression level of HER-2 gene in the same pathological stage gastric cancer,and discuss the feasibility of HER-2 gene being the prognostic indicator.MethodsThe expression of HER-2 in gastric cancer was detected by immunohistocehmical technique and analyzed in relation with the pathological stage and prognosis of the patients.ResultsThe total positive rate of HER-2 in gastric cancer was 33.64％ (37/110).In stage Ⅱ,the weakly and strongly positive rates of gastric cancer were 21.31％ ( 13/61 ) and 9.84％ (6/61).In stage Ⅲ,the weakly and strongly positive rates of gastric cancer were 20.41％ (10/49) and 16.33％ (8/49).In the same pathological stage,the survival rate of patients with negative HER-2 expression was higher than weakly positive ones.And the survival rate of patients with strongly positive HER-2 expression was the lowest.The difference had statistical significance (P ＜ 0.01).ConclusionThe prognosis of patients in the same stage was correlated with the expression level of HER-2,which can be used to evaluate the biological behavior and prognosis of gastric cancer.