Abstract: Objective:To investigate the efficiency of two-dimensional ultrasound, color Doppler ultrasound, and computerized tomography (CT) in diagnosing thyroid microcarcinoma.Methods:Included in were 213 patients with thyroid masses who visited our hospital between June 2017 and June 2019 and were suspected to have thyroid microcarcinoma. All subjects underwent CT, color Doppler sonography and two-dimensional ultrasonogarphy. Using pathological diagnosis as the gold standard, the diagnostic efficiency of CT, color Doppler and two-dimensional ultrasound alone or in combination for thyroid microcarcinoma was compared.Results:Among the 213 patients with suspected thyroid microcarcinoma, 178 were positive for thyroid microcarcinoma by pathology, 107 by two-dimensional ultrasound, 145 by color Doppler ultrasound, 160 by CT, and 175 by combination of CT, color Doppler ultrasound, and two-dimensional ultrasound. The diagnostic efficiency of Color Doppler ultrasound and CT was better than that of two-dimensional ultrasound for thyroid microcarcinoma ( P<0.05) . Color Doppler ultrasound and CT did not differ significantly in diagnostic efficiency for thyroid microcarcinoma ( P>0.05) . Combination of CT, color Doppler ultrasound, and two-dimensional ultrasound led to better diagnostic efficiency for thyroid microcarcinoma than did any alone ( P<0.05) . Conclusion:Combination of two-dimensional ultrasound, color Doppler ultrasound, and CT offers significantly higher diagnostic accuracy and yields for thyroid microcarcinoma compared with any alone, and therefore appears to be clinically useful.