ObjectiveTo summarize and analyze the clinical characteristics of patients with thyroiditis who would be misdiagnosed with thyroid tumor easily. MethodThe clinical data of 19 patients with thyroiditis who were misdiag-nosed with thyroid tumor in our department from 2009 to 2012 were analyzed retrospectively. ResultsAll of 19 patients underwent surgery, among which 8 cases were diagnosed with chronic lymphocytic thyroiditis after operation, 10 cases diagnosed with subacute thyroiditis, and 1 case diagnosed with suppurative thyroiditis.Different surgery program such as the biopsy or wedge resection was adopted to the subacute thyroiditis and the chronic lymphocytic thyroiditis respec-tively. ConclusionSometimes, it is very difficult to distinguish atypical thyroiditis from thyroid tumor so that we must pay attention to the patients who had nontumorous characteristics in order to decrease the misdiagnosis.