Objective To summarize and analyze the epidemiological and clinical characteristics of patients with subacute thyroiditis (SAT),so as to provide a basis for prevention and treatment of the disease.Methods The epidemiological and clinical datas of 121 SAT patients,who were treated at the Shandong Provincial Institute for Endemic Disease Prevention and Control in 2015,were collected.The SAT patient's age,sex,lived in urban or rural areas,occupation and time of onset distributions were analyzed retrospectively.According to the clinical manifestations,the SAT patients were divided into types Ⅰ (mild/nodule type),Ⅱ (medium/normal),Ⅲ (severe/hyperthyroidism),and Ⅳ (delay),and clinical manifestations,auxiliary examination findings,treatment and outcome were summarized.Results Average age of the 121 cases of SAT patients was 41.36 years old,the youngest was 10 years old and the oldest was 76 years old.Most of the patients were 30-＜ 50 years old,which was accounted for 55.37％ (67/121).Most of the patients were female,which was accounted for 90.08％ (109/121).Most of the patients lived in rural areas,which was accounted for 59.50％ (72/121).Majority of the SAT patients were farmers,which was accounted for 43.80％ (53/121).Most onset of the disease was in November,accounted for 19.83％ (24/121),and the least was in June,accounted for 2.48％ (3/121),the peak of the incidence of SAT lied in autumn,and it was sporadic in the rest of the year.From the clinical classification,the mild type (61) and the medium type (46) were the largest part,a total of 107 cases,accounted for 88.43％ (107/121);while the severe type had 5 cases,accounted for 4.13％ (5/121);the delay type had 9 cases,accounted for 7.44％ (9/121).The clinical manifestations were as follows:anterior neck discomfort was 109 cases,accounted for 90.08％ (109/121);sore throat was 93 cases,accounted for 76.86％ (93/121).Auxiliary examination findings were as follows:thyroid iodine taken rate reduced in 121 cases,accounted for 100.00％ (121/121);thyroid nodule 96 cases,accounted for 79.34％ (96/ 121);total number of white blood cells increased in 52 cases,accounted for 42.98％ (52/121);neutrophil increased in 61 cases,accounted for 50.41％ (61/121);blood sedimentation significantly speed up in 49 cases,accounted for 40.50％ (49/121).All of the 121 patients were cured.Conclusions Majority of the patients are female,young aduhs and farmers.The peak of the incidence of SAT lies in autumn.The proportion of mild,medium type is the highest,we suggest this disease should be early diagnosis and treatment.