Objective To explore the value of CT in the differential diagnosis of inflammatory thyroid nodules and thyroid carcinoma. Methods A total of 12 cases of inflammatory thyroid nodules and 23 cases of thyroid cancer were collected between March 2012 and October 2017, and the morphology, size, edge, position, internal condition, number, calcification, peripheral clearance, lymph node enlargement and density and degree of enhancement of the two types of lesions were analyzed and measured, and the differences of CT manifestations of the two lesions were compared. Results Thyroiditis is more diffuse enlargement, the edge of the nodules are fuzzy, multiple, morphological rules and less calcified or for change, the more bulky calcification, less sac involving spondylolysis, cervical lymph node enlargement is not obvious, much as strengthening and delay strengthening. Thyroid cancer is boundary is not clear, form more irregular, single, fine granular or tip necrosis capsule calcification, see more, less involvement spondylolysis, neck lymph node enlargement, uneven density, strengthening the obvious and uneven, visible "bite of bread" or "contour connection interruption sign" and "islands", etc. Thyroid inflammatory nodules and thyroid cancer lesions were not significantly different in age, gender, edge, lesion maximum diameter(P＞0.05). In lesions form, number, cystic change and calcification, isthmus, involvement and cervical lymph node enlargement and the enhancement (evenness) is obviously different, the difference was statistically significant (P<0.05). Conclusion CT has high value in the differential diagnosis of inflammatory thyroid nodules and thyroid carcinoma, and it is worth promoting the application in clinical practice.