Abstract: Objective To compare effect of ultrasound-guided microwave ablation versus surgery in treatment of thyroid papillary microcarcinoma. Methods A total of 240 patients with thyroid papillary microcarcinoma were selected as research objects, and were divided into observation group and control group according to the principle of patients' willingness, with 120 cases in each group. The operation condition, stress index, thyroid index, complications and surgical effects were compared between the two groups. Results The operation time and hospitalization time in the observation group were significantly shorter than those in the control group, the amount of bleeding and hospitalization expenses in the observation group were significantly less than those in the control group(P<0.05); the serum malondialdehyde(MDA)on the fist postoperative day in the observation group was significantly lower than those in the control group, the superoxide dismutase(SOD)was significantly higher than those in the control group(P<0.05); after 1 month after operation, the thyrotropin(TSH)in the observation group was significantly lower than operation before(P<0.05), there were no significant differences in free triiodothyronine(FT₃)and free thyroxine(FT₄)in the observation group compared to operation before(P>0.05). after operation 1 month, the TSH in control group was significantly higher than that before operation, FT₃ and FT₄ were significantly lower than those before operation(P<0.05); the total incidence of postoperative complications in the observation group was significantly lower than those in the control group(P<0.05); after 12 months of operation, there was no recurrence- of nodules and cervical lymph node metastasis in both groups, and the effective rate was 100%; after 3,6, 9 and 12 months of operation, thyroid nodule volume was significantly smaller than operation before(P<0.05). Conclusion Compared with thyroidectomy, the ultrasound-guided microwave ablation for papillary thyroid microcarcinoma has the advantages of fewer traumas as well as stress response, faster recovery and fewer complications, and it can better retain thyroid function, and is similar in curative effect to surgery.