Abstract: Objective To investigate the prognostic significance of androgen receptor(AR) in patients with invasive breast cancer after modified radical mastectomy.Methods A total of 515 patients who were admitted to the Affiliated Hospital of Xuzhou Medical University from July 2016 to November 2017 were selected. Their expression of AR, estrogen receptor(ER), progesterone receptor(PR), human epidermal growth factor receptor-2(HER-2), cytoproliferating nuclear antigen(Ki-67), tumor suppressor gene(P-53), cytokeratin 5/6(CK5/6), topoisomerase Ⅱ(TOPO-Ⅱ), and epidermal growth factor receptor(EGFR), and the relationship between AR expression and clinicopathological factors and prognosis was analyzed.Results Compared with patients in the AR-negative group, those in the AR-positive group were more likely to be low histological grade(grades 1-2), ER positive, PR positive, TOPO-Ⅱ negative, CK5/6 negative, and EGFR negative, with statistical difference(P<0.05). In patients with ER(+)/HER-2(-), ER(+)/HER-2(+) breast cancer, AR-positive patients showed longer disease-free survival(P<0.05). In contrast, in patients with ER(-)/HER-2(+) and ER(-)/HER-2(-) breast cancer, AR expression was not associated with disease-free survival(P>0.05).Conclusions AR has different prognostic significance for different breast cancer subtypes. AR positivity is a good prognostic factor in ER-positive tumors.