To investigate the feasibility and clinical effect of sentinel lymph node biopsy（SLNB）for breast cancer under endoscopy.

The pathological data of 300 SLNB breast cancer patients from October 2016 to January 2019 were retrospectively analyzed and divided into endoscopic group（n=72，endoscopic biopsy）and open group（n=228，open biopsy）according to different biopsy methods. Sentinel lymph nodes were detected by methylene blue alone and methylene blue radionuclide combined method. Statistical software SPSS 21.0 was used for data analysis. Perioperative indicators and other measurement data were expressed by（

The perioperative indexes of intraoperative blood loss，operation time，hospitalization time，first day drainage volume and extubation time were significantly lower in the observation group than in the control group（P<0.05）. The sentinel lymph node detection rate was 91.7%（66/72）in the endoscopic group and 89.9%（205/228）in the open group，and there was no significant difference between the two groups（P>0.05）. The sensitivity，accuracy and false negative rate of sentinel lymph node detection in endoscopic group were 87.5%，96.7% and 12.5% respectively. The sensitivity，accuracy and false negative rate of SLN in the open group were 89.7%，97.1% and 10.4%，respectively. The incidence of subcutaneous local effusion in endoscopic group（5.2% vs 0.0%）was higher than that in open group.（P<0.05）.

Endoscopic sentinel lymph node biopsy and open sentinel lymph node biopsy have similar detection rate，aesthetic effect is better，the method is feasible.