Objective: To investigate the approach for the preservation of the intercostobrachial nerve (ICBN) during endoscopic axillary lymph node dissection (EALND) for breast cancer and its significance. Methods: The clinical data of 98 patients with stage I or II breast cancer undergoing EALND procedures during May 2010 to September 2012 were collected, and then the data from 52 patients with ICBN preservation (preservation group) were compared historically to those from 46 previously treated patients without ICBN preservation (non-preservation group). Results: The post-mastectomy incidence of abnormal skin sensation (numbness and/or pain) in the upper arm in preservation group was 7.69% (4/52) and in non-preservation group was 82.61% (38/46) respectively, and difference between them had a statistical significance (P<0.05). The symptoms of abnormal skin sensation in the upper arm lasted for more than one year in the 38 cases in non-preservation group, and were considerably milder in the 4 cases in preservation group, among whom the symptoms were completely relieved in 3 cases within 3 months and within 6 months in 1 case. Conclusion: Sufficient liposuction is the key for preserving ICBN during EALND for breast cancer, and ICBN preservation can reduce the occurrence of upper arm numbness and/or pain after surgery and improve the patients’ quality of life.