Purpose: The purpose of this study was to evaluate the CT findings of thyroglossal duct cysts Materials andMethods: Sixteen patients with pathologically proved thyroglossal duct cysts were included in the study. CT scanswere assessed retrospectively for shape, size, location, density of the central portions, septations, rimenhancement, changes in the adjacent fascial planes and investment within the strap muscles in the infrahyoidcysts. Result: Thirteen cases of thyroglossal duct cysts were seen as round or oval cystic masses, two cases ofthem were seen as irregular-shaped lobulated cystic masses, and one case was seen as ovoid soft tissue mass. Thecysts were from 1.4 to 5.7 cm in diameter(mean, 2.6 cm). The cyst was infrahyoid in 15 cases and suprahyoid in onecase. The cyst was located in midline in eight cases, off midline in four cases, and both midline and off midlinein four cases. The density of the central portions ranged from 15 to 82HU(mean, 32HU). Septations were noted infour cases. Rim enhancement was seen in 14 cases(93%), and heterogenously enhancing soft tissue mass was seen inone case. In four cases, abnormal fascial planes were observed. All but one of the infrahyoid cysts(14/15) wereembedded within the strap muscles, and one case of them was located anteriorly to strap muscles. Conclusion: CTpermits one to make the diagnosis a thyroglossal duct cyst with a high degree of accuracy, as it can differentiatethyroglossal duct cysts from the other anterior neck masses by their typical location, characteristic morphology,and investment within the strap muscles.