Objective To study spiral CT features and pathological basis of nodular goiter ,so that to improve the diagnostic accuracy of nodular goiter.Methods CT findings in 34 patients with nodular goiter confirmed by pathology were retrospectively analyzed and compared with pathological findings. Results Thyroid density in the patients with NG was lower than that in the normal. There was no statistically significant difference in the density between single and multi-NG. Most lesions(28/34) were multiple, round or oval, with different size and smooth edges. The density of majority lesions was lower than nearby normal tissue. Most lesions (27/34) were uniform in density. Central necrosis(5/34)often appeared in the bigger lesions(diameter＞3.0 cm). The CT value of the lesions was increased (47.1±42.2) HU after enhancement,but lower than surrounding thyroid tissue. Calcifications in the lesions(6/34)were puncticular,plaque or crustiform. Single or multiple cystic-solid or solid nodules could be seen in pathology, without a continuous capsule in the majority. Some patients (5/13) with single NG shown on imaging study were multi-NG in the pathology. Three cases of diffuse NG showed by CT were malignant in pathology. Conclusion There are certain characteristics for NG on spiral CT. Comprehensive evaluation may improve the accuracy of CT diagnosis.