Abstract: Objective : To investigate the clinical and biological features of papillary thyroid microcarcinoma. Methods : Data from 383 patients with papillary thyroid carcinoma seen in our hospital between January 2003 andDecember 2006 were retrospectively reviewed. WHO guidelines for papillary thyroid microcarcinoma were em-ployed. Results : Of these 383 patients, 110 (28.7%) cases were identified as microcarcinoma. Other histologi-cal variants were also observed in those cases classified as microcarcinoma. The rates of diffuse sclerosingvariant and tall cell variant were 20.9% and 3.6%, respectively. No significant difference was found in age orgender between microcarinoma and conventional papillary thyroid carcinoma (P>0.05). The rate of cervicallymph node metastasis in patients with microcarcinoma was 20.0%, lower than that in patients with conven-tional papillary thyroid carcinoma (P<0.05). The rate of metastasis to section VI was 90.9%. No distant metas-tasis was found in patients with microcarcinoma. Conclusion : Although the rate of cervical lymph node metas-tasis from papillary thyroid microcarcinoma is low, careful monitoring should be upheld because aggressivevariants exist. All cases of microcarcinoma cannot be considered and treated as stage I carcinoma. Individual-ization is critical in the treatment of papillary thyroid microcarcinoma.