Objective To investigate the correlative factors of sentinel lymph node(SN) metastasis status in breast cancer.Methods The clinical data of 115 patients with breast cancer who underwent sentinel lymph node biopsy(SLNB) and axillary lymph node dissection(ALND) during June 2004 through April 2006 were retrospectively analysed.The SN metastasis were evaluated with regard to tumor size(≤2cm, 2.1cm~4cm)and C-erbB-2、p53、nm23、ER、PR status.Results Of the 115 patients SN was identified in 110(95.65%).An average of 1.97 SNs were examined per patient.Ninety-five(86.37%)of 110 patients were correctiy diagnosed in SN and AN.Thirty-six(37.89%)of 95 patients were SN positive,and 59(62.11%)were SN negative.Among the patients,SN metastasis rate in tumors 2.1cm~4cm((50.94)%) in diameter was highter compared with those ≤2cm(23.43%) in size(P0.05).Conclusions Tumor size and C-erbB-2 status were significantly associated with SN metastasis and may be used to predict SN metastasis in invasive breast cancer.