This study is to investigate the accuracy of Sentinel Lymph Node Biopsy (SLNB) in predicting axillary lymph node metastasis and its application in breast conserving surgery for early breast cancer. The clinical data of SLNB of 448 patients were retrospectively analyzed. The patients with negative result of SLNB were not performed with Axillary Lymph Node Dissection (ALND) (experimental group), but treated with breast conserving surgery. The effect of experimental group was compared with traditional operation (control group). 448 patients with early breast cancer were examined with SLNB. The result showed that 439 cases were successfully detected, 9 cases were not detected, and 15 cases were detected with false negative SLNB among 448 patients with early breast cancer. Detection rate was 98.0% (439/448). Sensitivity was 92.8% (194/209). Accurate rate was 95.7% (332/347). False negative rate was 7.2% (15/209). The operation time, bleeding volume, extubation time, total flow rate and incidence of complication in the experimental group were less than those in the control group. The difference between the two groups was quite significant (P<0.05). And the breast cosmetic effect was good after operation. It is feasible for the patients with early breast cancer to be treated with breast conserving surgery combined with SLNB. The operation is simple, the incidence of complication is low, and the recovery is rapid.