Thyroid gland surgery today is not saddled with high incidence of main complications. Miscellaneous surgical institutions with different surgical approach, operative technique and radicality have published reports with great discrepancy in incidence of complications, analyzing them with different methods of diagnosis and result evaluation. In the same way it is well known that higher latitude of operative procedure gave better control of thyroid diseases, but it can be accompanied with more complications. All of that motivate us to analyze complications of operative treatment in our patients under well known criteria, with hypothesis that higher radicality of operative procedure do not increase incidence of complications, and that this incidence is in correlations with results published in world literature. Aim of this nonrandomized study was to analyze results of operative treatment for huge number of consecutively operated patients in our teaching hospital, to analyze and compare results according to group of diseases and operative procedures, and to compare final results with results published in the world literature. Complications of operative treatment were analyzed retrospectively for period 1988-1997 (Group I) and prospectively in period 1998-2002 (Group II). Operations were performed by 20 surgeons and 20 young surgeons during their education. We have analyzed only complications during first 30 days after operation. In Group I there was 1425 patients with 1451 operations (192 thyroid malignancies, 247 hyperthyreosis, 98 reoperations, 13% thyroidectomies and 14.8% lobectomies), with complication rate of 14.3%. Most common complication was recurrent laryngeal nerve injury in 9.3% patients or 6.3% according to number of exposed nerves (nerve at risk), then postoperative hypocalcemia with rate of 4.7% (persistent in 1.3%). In Group II in 675 patients there was 687 operations (96 thyroid malignancies, 111 hyperthyreosis, 35 reoperations, 36.6% thyreoidectomies and 25% lobectomies), with complication rate of 10.7%. Most common postoperative complication was hypocalcemia with 5% rate (persistent in 0.7%), then recurrent laryngeal nerve injury in 4.4% patients or 2.9% according to number of exposed nerves. Incidence of recurrent laryngeal nerve injury in Group II is less frequent than in Group I, highly statistically significant (p < 0.01), while for other complications there is no statistically significant difference. Totally for both groups there was 0.7% tracheotomies, postoperative bleeding in 1.1% of patients, wound hemathoma in 0.5%. wound infections in 0.9%, pneumonia in 0.5%, mortality 0.5% and most common cause of death (8/11) was problem with respiration, Airway obstruction. In Group II complications were less frequent in total thyroidectomies in relation to lobectomy with contra lateral subtotal lobectomy. In both groups and totally incidence of complications was higher in reoperations, in patients with more extensive operative procedure, in malignant diseases and hyperthyreosis. In thyroid gland surgery more extensive operative treatment with improved operative technique (micro dissection, recurrent laryngeal nerve visualization and parathyroid gland preservation), in our teaching hospital, do not have influence on incidence of postoperative complications, even recurrent laryngeal nerve injury was significantly less frequent. This results are in correlation with published results of similar hospitals around the world.