【Abstract】Objective Stromal cell-derived factor-1(SDF-1, CXCL12) is a member of the CXC subfamily of chemokines which, through its cognate receptor (CXCR4), plays an important role in tumor invasion and metastasis. This study analyzed quantitatively the expression of SDF-1 and its relation with clinicopathologic feature and clinical outcome in human breast cancer.Methods Expression of SDF-1 mRNA in 8 breast cancer cell lines, an endothelial cell line HECV and a fibroblast cell MRC5 was studied by using RT-PCR. In addition, the expression of SDF-1 was investigated at both protein (immunohistochemistry) and mRNA(real-time PCR) levels in a group of human normal mammary(n=32) and tumour tissues(n=120). Results SDF-1 expression was identified in MRC5, MDA-MB435s, MDA-MB436, MCF7 cell lines, breast tumour and normal tissues. Significantly higher level of SDF-1 was seen in lymph node positive than in lymph node negative tumours (399.00±210.00 vs 0.89±0.47), P=0.048. The level of SDF-1 expression in patients who developed local recurrence or metastasis, or patients who died of breast cancer was higher than in patients who were disease free as well, (670.00±346.00 vs 0.83±0.35), P=0.01. It was most notable that level of SDF-1 was significantly correlated with over survival (P=0.01) and incidence free survival (P=0.035, by Cox proportion analysis).Conclusion SDF-1 is a factor that is expressed in both stromal cells and some breast cancer cells. Its level are correlated with lymph node involvement, prognosis and survival in patients with breast cancer. SDF-1 may therefore have a potential prognostic value in breast cancer.