Objective To observe the effects of low-dose left thyroid hormone on postoperative recovery of patients with benign thyroid nodules.Methods 95 patients with benign thyroid nodules were selected and divided into 2 groups using a random number table method.47 cases in the conventional group were received ultrasound-guided microwave ablation treatment,while 48 cases in the combined group were received low-dose left thyroid hormone in combination with the conventional group before surgery.The thyroid ultrasound parameters,endocrine metabolism indicators,oxidative stress indicators,postoperative rehabilitation progress,and incidence of adverse reactions were compared between two groups of patients.Results Under different treatment regimens,the thyroid volume(JV),diameter of thyroid isthmus(JD1),and the maximum cross-sectional area of thyroid nodules(JD2)of the combined group were lower than those of the conventional group 24 h before surgery,showing a statistically significant difference(P<0.05);the total thyroxine(FT4)of the combined group was higher than that of the conventional group,while the levels of total triiodothyronine(FT3),thyroid stimulating hormone(TSH),glutathione(GSH),glutathione peroxidase(GPX),and glutathione reductase(GR)were all lower than those of the conventional group(P<0.05).The postoperative drainage volume and drainage time,thyroid function recovery time,and hospital stay of the combined group were lower than those of the conventional group(P<0.05).There was no statistically significant difference in the incidence of adverse reactions between the two groups(P>0.05).Conclusion The application of levothyroxine as an adjuvant therapy before microwave ablation can reduce the volume of nodules and create favorable surgical conditions for patients,which has a positive significance in improving thyroid function,enhancing the body's antioxidant capacity,and accelerating the postoperative recovery process of patients;Low doses of levothyroxine do not significantly increase the risk of adverse reactions and are relatively safe.