The aim of this study is evaluation of a role of conventional ultrasonography, color flow-Doppler and color Doppler energy sonography in preoperative diagnosis of thyroid nodules. Also the benefits of complex ultrasonography in early postoperative period were estimated. For this purpose 144 patients with thyroid nodules were investigated before and after thyroid surgery. Ultrasound data was compared to the results of morphological investigation of the thyroid tissue biopsies. We concluded that use of Doppler methods of sonography before thyroid surgery provided valuable information about characteristics and localization of thyroid nodules, rational extent of operation, and therefore improved results of thyroid surgery. Benefits of conventional ultrasonography, color flow-doppler and color Doppler energy sonography in the postoperative period is also apparent, because sometimes thyroid surgery is not adequate and a re-operation should be performed.