Abstract: Objective:To explore the clinical value of two-dimensional and color Doppler ultrasonography in the diagnosis of thyroid Carcinoma.Methods:Forty-two cases with thyroid carcinoma were confirmed by pathological examination.The size of the thyroid,echo,mass's size,shape,position,number,internal echo intensity and evenness,the calcification changes,the blood distributioncolor and the resistance index of blood of all cases were measured.Results:In all patients,the lumps of 32 cases were abnormity,the heterogeneous echo of lumps of 34 cases were low,28 cases had small calcification,37 cases had abundant blood flow and the resistance index of blood of 30 cases were less than 0.7.Conclusions:The performances of ultrasonography of thyroid carcinoma have definite features.It has important clinical value to diagnose thyroid carcinoma.