Objective To evaluate the clinical significance of sentinel lymph nodes biopsy (SLNB) in breast cancer patients after neoadjuvant chemotherapy. Methods SLNB was performed in sixty primary breast cancer patients after neoadjuvant chemotherapy using a combination of 99mTc- Rituximab and patent blue. SLN was examined by routine pathologic examination and immunohistochemistry. Routine axillary lymph node resection was performed after SLNB. Results The successful rate of SLNB was 95% (57/60). Twenty-three cases of SLN (40% ) were metastasis positive, including 18 positive cases detected by HE staining and 5 by immunohistochemistry. SLN was the only metastasis lymph nodes in 14 out of 23 cases. One case was of false negative metastasis by SLN. The sensitivity and accuracy of SLNB were 96% (23/24) and 98% (56/57), respectively. The specificity was 100% (33/33) , the false negative rate was 4. 3% (1/23) with the negative predictive value being 97% (36/37). The positive predictive value was 100% (24/24). Internal mammary sentinel lymph node lymphoscintigraphy were positive in 11 cases but all the cases were negative in metastases by pathologic examination. Conclusion The combination of isotope imaging agent and patent blue is suitable for primary breast carcinoma after neoadjuvant chemotherapy. Internal mammary sentinel lymph node biopsy is less clinically important.