Objective: To compare the efficacy of ultrasonic scalpel and traditional electrocautery for mastectomy and axillary lymph node dissection in breast cancer surgery. Methods: The relevant randomized controlled trials (RTCs) were collected by searching the national and international databases. After literature screening, quality assessment and data extraction, Meta-analysis was performed by using RevMan 5.2 software. Results: Eight RTCs were finally included, with a total sample size of 604 cases comprising 300 cases in ultrasonic scalpel group and 304 cases in electrocautery group. Results of Meta-analysis showed that in ultrasonic scalpel group compared with electrocautery group, the operative time had no significant difference (WMD=6.20, 95% CI=-5.02–17.41, P=0.28), but the intraoperative blood loss (WMD=–61.42, 95% CI=–83.76––39.09), postoperative drainage volume (WMD=–374.92, 95% CI=–453.90––295.95), drainage time (WMD=–3.30, 95% CI=–5.10––1.49), and the incidence of subcutaneous fluid collection (RR=0.51, 95% CI=0.38–0.68) were all significantly decreased (all P<0.05). Conclusion: In breast cancer surgery, use of ultrasonic scalpel is superior to that of electrocautery in respects of intraoperative bleeding control, and reducing postoperative drainage and incidence of subcutaneous fluid collection.