Objective To observe and analyze the CT features of thyroid lesions in pulmonary CT. Methods A total of 450 cases of thyroid lesions were followed up in 3750 cases, CT values of thyroid, thyroid nodules, peripheral lymph nodes and other CT features were analyzed. A total of 100 consecutive patients with normal thyroid as control group. Radiation dose for the subjects. comparison of the radiation dose using t test; and the CT values of thyroid in each group were compared with the analysis of variance. Results There was no significant difference in the radiation dose among the subjects with or without thyroid in the pulmonary CT. In 450 cases of patients, goiter and nodular goiter is the most common, followed by thyroid adenoma, thyroiditis, Graves' disease and thyroid malignant lesions. 85 cases of thyroiditis, the gland of CT values was significantly lower, the average is about (54.2±15.3) HU (P<0.01). 35 cases of Graves' disease, the density decreased, without nodules. 210 cases of Goiter and nodular goiter. 20 cases of goiter, 190 cases of nodular goiter, and all cases have 270 nodules. 24 cases have nodules lesions, 59 cases have nodular calcification. Thyroid adenoma in 92 cases, 84 cases of solitary nodules or masses, 8 cases of unilateral multiple nodules, nodules can be cystic changes (45 cases), calcification (9 cases). Thyroid malignant lesions in 28 cases, 17 cases of irregular or granular calcification, 10 cases of cystic changes (3 cases of the wall nodules), 12 cases of lymph nodes, the lesions and normal thyroid gland and surrounding structure is not clear. Conclusion There has a higher probability of showing and found thyroid lesions in the pulmonary CT. and thyroid lesions had characteristic features on CT.