Background: The objectives of the study were to explore the real world treatment of T3 breast cancer (maximum diameter of tumor >5 cm). Methods: We selected T3 breast cases diagnosed from 2011 to 2017 in the Chinese Society of Clinical Oncology (CSCO) breast cancer (BC) database. These cases were categorized into two groups: the neoadjuvant chemotherapy (NAC) group and the non-NAC group. Adjusted hazard ratios for known predictors of event-free survival (EFS) using Kaplan-Meier and Cox proportional hazards regression. Results: The study included 868 patients: for their initial therapeutic strategy, 49.0% (425/868) of patients chose NAC and 51.0% (443/868) chose surgery (non-NAC group). Compared with the non-NAC group, patients in the NAC group were correlated with clinical lymph node positive, hormone receptor (HR) negative, and human epidermal receptor growth factor 2 (HER2) positive. For the non-NAC group, only 87.1% (386/443) of patients were pathologic T3 after surgery, and the overestimation of clinical examination of tumor lesion was 12.9% (57/443). In addition, there was no significant difference in EFS between the NAC group and non-NAC group (HR =0.82, 95% CI: 0.64-1.05). However, for T3 breast cancer patients with positive lymph nodes, and HR-negative and HER2-positive tumors, the NAC group had a better survival rate than the non-NAC group. Cox proportional analysis showed that lymph node negative, HER2-negative status, and neoadjuvant chemotherapy were associated with a longer survival time. Conclusions: For T3 breast cancer patients with positive lymph nodes, and HR-negative and HER2-positive tumors, neoadjuvant chemotherapy should be applied first.