Abstract: Objective To investigate the expression of HOXD3 in triple-negative breast cancer （TNBC） and its relationship with clinical pathological factors and prognosis. Methods The expression of HOXD3 was detected in 89 TNBC tissues by immunohistochemical staining and compared with the clinicopathological features and the prognosis. Results The positive expression rate of HOXD3 in TNBC was 69.7%（62/89）， and it was closely associated with histological grade and NPI. The medium disease-free survival and overall survival of patients with positive HOXD3 expression were lower than those of patients with negative HOXD3 expression. Univariate and multivariate analyses showed that HOXD3 was an independent unfavorable prognostic factor for patients with TNBC. Conclusion HOXD3 can be used as a potentially useful prognostic marker for TNBC.