Aims and Objectives: We aimed to determine whether the modified bipolar cutting & coagulation system resulted in shorter operative time and less intraoperative blood loss and less postoperative complications compared to harmonic FOCUS for total thyroidectomy. Method: From September 2016 to December 2019, a total of 305 inpatients underwent total thyroidectomy in our center were randomly divided into trial group(n=155) and control group(n=150) and the surgical results were analysed prospectively. Results: The operative time, intraoperative blood loss, specimen weight, the classification of cervical lymph node dissection and the mean number of dissected lymph nodes indicated no statistical difference between two groups(P＞0.05). The rate of intraoperative parathyroid autotransplantation was 32.7%(49/150) in the control group, significantly higher than 16.1%(25/155) in the trial group (P=.001). The levels of serum PTH in the trial group at day 1,3 and 5 were significantly lower than those in the trail group(P＜0.04). The rate of transient RLN injury was 8.0%(12/150) in the control group, significantly higher than 2.6%(4/155) in the trail group(P=.041). The rate of postoperative transient hypocalcemia were 33.3% (50/150) in the control group, more than 14.8%(23/155) in the trail group statistically((P=.000). Conclusions: The modified bipolar cutting & coagulation system means safe, less damage and less complications and deserves popularizing for thyroid surgery.