Objective · To study the imaging of subcutaneous lymph-vessels and lymph-nodes in sentinel lymph node biopsy (SLNB) with different concentrations of indocyanine green (ICG), and to find the best concentration to improve the success rate of SLNB.   Methods · A total of 339 primary breast cancer patients with clinical negative axillary lymph node were enrolled in the study. Double tracer method [ICG and methylene blue (10 mg/ mL)] was used for sentinel lymph node biopsy. 1.25 mg/mL ICG was diluted to difference concentration. The injection volume was 1 mL for ICG and 1 mL for methylene blue. The imaging of subcutaneous lymph-vessels and lymph-nodes and the success rate of SLNB were recorded after injection of different concentrations of ICG.  Results · The concentration of ICG had significant effect on lymph-vessels and lymph-nodes imaging rate and SLNB success rate (P=0.001). In the group that breast tumors not located in the external upper quadrant (needle biopsy or excisional biopsy) and tumor located in the external upper quadrant without excisional biopsy (needle biopsy), concentration of ICG reached 80% subcutaneous lymph-vessels imaging rate is 0.723 mg/mL (95% CI 0.595-0.915 mg/mL). In this group, in this concentration range, the imaging rate of subcutaneous lymph node was 28%-53%, and the success rate of SLNB was 88%-92%. In the group that breast tumors located in the external upper quadrant and had been resected, the imaging rate of subcutaneous lymph-vessels and lymph-nodes was 50%-69% and 20%-42%, respectively, and the success rate of SLNB was 76%-81%. The difference of subcutaneous lymph-vessels imaging rate between two groups was statistically significant (P=0.014), but the difference of lymph-nodes imaging rate and SLNB success rate had no significance (P=0.628, P=0.232).  Conclusion · Using double tracer (ICG and methylene blue) in SLNB is simple and feasible. The best concentration of ICG is 0.723 mg/mL, which can improve the imaging rate of lymph nodes and lymph nodes.