Objective To investigate the differences in clinicopathological characteristics and prognostic survival of human epidermal growth factor receptor 2 (HER2) high expression, HER2 low expression and HER2 negative breast cancer. MethodWe retrospectively collected 1 560 female breast cancer patients who underwent surgical treatment at the Department of Breast and Thyroid Surgery in Renmin Hospital of Wuhan University between January 8, 2010 and December 31, 2015, and divided them into high expression group, low expression group and negative group according to HER2 expression, to compare the differences in clinicopathological characteristics among the three groups of breast cancer patients and to explore the factors influencing prognosis. Results The proportions of histological grade Ⅲ, tumor diameter >2 cm, lymph node metastasis, TNM stage Ⅲ, Ki67 high expression, and hormone receptor negative expression were higher in the high expression group than those in the low expression group and negative group (P<0.050); the proportions of histological grade Ⅲ, tumor diameter >2 cm, lymph node metastasis, and TNM stage Ⅲ were higher in the low expression group than those in the negative group (P<0.050). However, the proportions of Ki67 high expression and hormone receptor negative expression were lower than those of the negative group (P<0.050). The 5-year disease-free survival rate were 85.6%, 80.3% and 74.5% for the high expression, low expression and negative group, respectively, and the 5-year overall survival rate were 90.4%, 86.0% and 80.7%, respectively. The results of multivariate Cox proportional hazard model showed that patients with high histological grade, late TNM stage, Ki67 high expression and weaker HER2 expression intensity had worse 5-year disease-free survival (P<0.050); patients with older age, high histological grade, lymph node metastasis, late TNM stage, Ki67 high expression and weaker HER2 expression intensity had worse 5-year overall survival (P<0.050). Conclusions The intensity of HER2 expression affects the 5-year disease-free survival and overall survival of breast cancer patients, and the higher the intensity of HER2 expression, the better the 5-year disease-free survival and overall survival, while the weaker the HER2 expression, the worse the 5-year disease-free survival and overall survival.