Background and purpose:The prognostic role of human epidermal growth factor receptor 2 (HER-2) remains controversial in patients with non-small cell lung cancer (NSCLC). This study aimed to evaluate the expression of HER-2 and its prognostic implication in patients with NSCLC.Methods:Four hundred and twenty-ifve NSCLC patients’ specimens were obtained from Zhejiang Cancer Hospital. HER-2 protein expression was determined by immunohistochemistry (IHC). The relationship between HER-2 and clinicopathological parameters and patients’ prognosis was analyzed by Chi-square test and COX proportional hazards regression model.Results:Eighty-three patients were positive expression of HER-2 (83/425, 19.5%). The expression of HER-2 was closely related with histological type (P=0.051), most patients with HER-2 positive were adenocarcinoma, then were squamous carcinoma or other histological types. However, HER-2 was not an independent prognostic indicator for the overall survival of patients with NSCLC.Conclusion:We found that the expression of HER-2 was closely connected with histological type, but it was not a predictive marker for the prognosis in patients with NSCLC.