Abstract: Objective Fine-needle aspiration cytology (FNAC) is a kind of direct and accurate test for thyroid disease. The aim of this paper is to analyze the clinical features of thyroid disease confirmed by FNAC in patients at different age, and improve the understanding and clinical diagnosis and treatment of thyroid diseases. Methods FNAC results and clinical data of 579 patients with thyroid disease in Endocrinology Department Peaking University First Hospital from August 2006 to January 2010 were analyzed retrospectively. The patients according to their ages were divided into teenage (age<20 years), youth (20-39 years), middle age (40-59 years), and seniors (age≥60 years). The clinical features were compared among the four groups. Results Female patients accounted for main part in all groups, the difference in sex was especially obvious in the youth group(the ratio of male to female was 1∶20.3), not obvious in the senior group (the ratio of male to female is 1∶3.8). There were more patients who had no symptoms in teenage and seniors when compared with the other two groups that were with more obvious clinical manifestations. The incidence of thyroid carcinoma in the teenage group was the highest (13.3%) among the all four groups. The most common pathological type was goiter in seniors group; however, the most common pathological type was Hashimoto thyroiditis in the other three groups, the difference was obviously. The histologic subtype analysis for the patients with Hashimoto thyroiditis showed that the ratio of eosinophil subtype of Hashimoto thyroiditis increased and lymphocyte subtype of Hashimoto thyroiditis decreased with the age of patients increasing. Conclusion There are some differences in thyroid disease distribution and clinical feature among the different age groups. The analysis of the clinical significance will improve the accurate diagnosis of thyroid disease, which is of certain clinical significance.