Objective: To study the clinical efficacy and safety of ultrasound guided lauromacrogol injection in the treatment of thyroid cyst.Methods: 160 cases of patients with thyroid cyst from January 2011 to December 2015 were selected and randomly divided into observation group and control group, 80 cases in each group. The control group received ultrasound guided percutaneous sclerotherapy injection of anhydrous ethanol, and the observation group received ultrasound guided percutaneous injection of lauromacrogol. After 3 months of treatment, the clinical efficacy in the two groups was followed up, and the adverse reactions of the two groups were compared.Results: The effective rate in observation group was 95.00 % (76/80), which had no difference with that in control group (93.75 %, 75/80) (P＞0.05). There were no serious adverse reactions, such as infection, cervical hematoma, bleeding and so on, in the two groups. There were 8 cases of mild pain in the right upper abdomen in observation group; and there were 16 cases of some drunken symptoms like increased heart rate, flushing, dry mouth, nausea and vomiting and 42 cases of patients with different degrees of pain in the course of treatment in control group. The adverse reaction occurrence rate in observation group was 10.00 % (8/80), which was significantly lower than that in control group (72.50 %, 58/80) (χ²=42.351, P＜0.05).Conclusion: Ultrasound guided lauromacrogol injection has the same clinical effect with anhydrous ethanol sclerotherapy in the treatment of thyroid cyst, but the adverse reactions incidence of ultrasound guided lauromacrogol injection is significantly lower than that of anhydrous ethanol sclerotherapy. It is a safe and effective sclerotherapy in treating thyroid cyst.