There is considerable controversy concerning the most appropriate surgical treatment of patients with differentiated thyroid carcinoma (DTC). Although some authors have advocated subtotal thyroidectomy, because of the decreased surgical morbidity and the lack of improved survival with a more extensive procedure, total thyroidectomy has been defended by others as a treatment of choice with lower morbidity. The aim of this study was (1) Evaluate the various surgical treatment modalities in management of DTC: the immediate and late results of incomplete, primary total and secondary completion thyroidectomy, as well as the duration of in-patient stay. (2) Find the relationship between complications and time of completion thyroidectomy. (3) Evaluate the various surgical treatment modalities in management of lymph nodes in DTC: relationship between neck dissection and complications, relationship between lymph node metastases and local recurrence, and (4) Three years survival rate after both primary total and secondary completion total thyroidectomy. The study included 54 patients with differentiated thyroid cancer. Patients were classified into 3 groups: Group I: including 30 patients, referred from outside clinics, who had undergone less than total thyroidectomy for thyroid swelling whose preoperative pathology was unknown and postoperative biopsy revealed DTC (18 cases of papillary carcinoma, 10 cases of follicular carcinoma and 2 cases of Hurthle cell carcinoma), (control group). Group II: Including 24 patients, for whom primary total thyroidectomy, central neck dissection, and radical neck dissection, when indicated , were done. Group III: Including the same 30 patients of group I, for whom reoperation with completion of total thyroidectomy (secondary total thyroidectomy), central neck dissection and radical neck dissection when indicated, were done. Our study found that (1) Post operative complications after primary total thyroidectomy were insignificantly different from that of incomplete thyroidectomy. (2) The remnant thyroid tissue in patients whom underwent less than total thyroidectomy had residual malignancies in 73.3 % of cases. (3) The risk of complications was significantly less after primary total thyroidectomy than completion surgery. (4) Initial treatment with total or near-total thyroidectomy decreases the incidence of recurrence in thyroid cancer. So we can conclude that: (1) Primary total thyroidectomy is the operation of choice for most patients with differentiated thyroid cancer when this operation can be safely performed. (2) Completion thyroidectomy as soon as possible after incomplete resection of the tumour may improve prognosis in differentiated thyroid cancer. (3) En-block resection of central ± lateral lymph nodes minimize local recurrence.