Abstract: Objective: To investigate the effects of harmonic scalpel combined with high-frequency bipolar coagulation on the recurrent laryngeal nerve paralysis and parathyroid injury in patients with thyroid carcinoma.Methods: Ninety-four patients with thyroid carcinoma were divided into the observation group and control group according to the random number table(47 cases each group).The observation group and control group were treated with harmonic scalpel combined with high-frequency bipolar coagulation and traditional operation,respectively.The surgery indicators,serology,and the recurrent laryngeal nerve paralysis and parathyroid injury between two groups were compared.Results: The intraoperative bleeding volume,operation time,incision size,drainage volume and hospitalization time in observation group were significantly less than those in control group(P<0.01).After operation,the level of blood phosphorus and incidence of hypothyroidism in observation group were significantly lower than those in control group(P<0.01 and P<0.05),and the levels of serum calcium and parathyroid in observation group were significantly higher than those in control group(P<0.01).Conclusions: Harmonic scalpel combined with high-frequency bipolar coagulation can help to optimize the operation indicators,stable serological indexes,and reduce the incidence of the recurrent laryngcal nerve paralysis and parathyroid injury.