OBJECTIVE: To evaluate the effectiveness and safety of Chinese herbal medicine (CHM) in the treatment of subacute thyroiditis. METHODS: Randomized controlled trials found in PubMed, Cochrane Library, and three Chinese databases were selected. RevMan 5.2 software was used to analyze the data with relative risk or mean difference, expressed with 95% of confidence interval. The quality of trials was assessed and graded the quality of evidence with GRADE profiler software. RESULTS: Twenty one studies were included. CHM was superior to Western Medicine (include prednisone and NSAIDs) in abating fever, relieving thyroid pain, recovering blood sedimentation, improving thyroid function, and preventing hypothyroidism (P<0.05), while no statistical differences were found in eliminating. goiter and reducing relapse rate. CHM plus Western Medicine were superior to Western Medicine in abating fever, relieving thyroid pain, eliminating goiter, and reducing relapse rate, while no statistical differences (P>0.05) were found in recovering blood sedimentation and improving thyroid function. The incidence of adverse reactions in treatment group was lower than that in control group (relative risk was 0.12 and 95% confidence interval was 0.03-0.51). The methodological quality of trials is generally poor with a high risk of bias. CONCLUSION: CHM (particularly CHM combined with Western Medicine) used to treat subacute thyroiditis may improve clinical symptoms and signs, reduce relapse rate, and alleviate the side effects of hormones. Due to poor methodological quality of included trials, further more high-quality studies are warranted to confirm the effectiveness and safety of CHM. (C) 2014 JTCM. All rights reserved.