Abstract: Objective: We intended to explore the correlation between diagnostic efficacy and histopathological types when dual-energy CT was applied in thyroid nodules, aiming to improve the accuracy of clinical diagnosis of thyroid cancer. Methods: We selected 224 patients with thyroid nodules diagnosed and treated by head and neck surgery in our hospital from January 2018 to October 2020. 148 cases with thyroid cancer formed observation group while 76 cases with benign thyroid nodules formed contrast group, then the preoperative CT manifestations were analyzed and compared with postoperative pathological results. Results: Among the 224 patients with thyroid nodules(148 cases with thyroid cancer formed the observation group while 76 cases with benign nodules formed the contrast group), 102 cases showed irregular nodules, 104 cases showed "peninsular" nodules, 106 nodules showed "enhanced remnant" signs, 89 cases showed "sand-lik" calcification and 84 cases with malignant nodules showed tumor invasion on surrounding tissues and organs. The ratio of standard iodine concentration and the slope of energy spectrum curve of benign thyroid nodules in arteriovenous stage were higher than those in malignant nodule group. We found significant differences between the two groups. Conclusion: The quantitative analysis of dual energy CT combined with CT signs hold certain characteristics for thyroid cancer discriminations. Different pathological types are closely related with iodine map and energy spectrum curve, which can lead to correct preoperative diagnosis and provide imaging basis for clinical diagnosis and treatment.