Objective：To analyze the cause of reoperation for differentiated thyroid carcinoma（DTC） and to explore the time and proper surgical patterns for the reoperation. Methods：Protocols of 147 patients undergoing reoperation for thyroid cancer from January 2002 to September 2009 were reviewed retrospectively with the study considering domestic and foreign literatures. The reoperation in－cluded total thyroidectomy for 66 cases，near-total thyroidectomy for 28 cases，subtotal thyroidectomy for 17 cases，unilateral lobecto－my for 1 case and palliactive mass excision for 17 cases. Central lymph node dissection or modified neck dissection for 116 cases were performed at the same time. Results：Pathological results after reoperation confirmed that the rate of residual carcinoma in thyroid tis－sue was 65.6%（82/125） and the rate of residual in lymph node was 62.9%（28/32）. The rate of temporarily recurrent laryngeal nerve injury was 0.68%（1/147） and of temporary hypocalcaemia was 6.8%（10/147），without permanent laryngeal recurrent nerve hurt or hypocalcaemia. Conclusions：Inadequate initial operation，local recurrence and cervical lymph node metastasis of thyroid cancer need reoperation sundoubtedly. The optimal treatment is total thyroidectomy with central compartment lymph node dissection or modified neck dissection.