【Abstract】 Objective To evaluate the value of threedimensional color power angiography combined with TIRADS standard in the diagnosis of benign and malignant thyroid nodules. Methods 98 patients with 105 thyroid nodules (benign 50, malignant 55), from December 2013 to December 2015 in Zunyi Medical College Affiliated Hospital were treated with conventional twodimensional ultrasound and 3DCPA examination. The thyroid nodules were classified with TIRADS score standard. The diagnosis value of 3DCPA and TIRADS were compared.Results Of 50 benign lesions with 3DCPA, there were 36 cases (72.0%) with surrounding blood flow distribution, 14 cases (28.0%) with inside and outside blood flow distribution, 43 cases (86.0%) with regular vessel walking and 7 cases (14.0%) with irregular vessel walking, 44 cases (86.0%) with spatial distribution symmetry and 6 cases (10.9%) with spatial distribution asymmetry. Of 55 malignant nodules with 3DCPA, there were 5 cases (9.1%) with surrounding blood flow distribution, 50 cases (90.9%) with inside and outside blood flow distribution, 6 cases (10.9%) with regular vessel walking and 49 cases (89.1%) with irregular vessel walking, 18 cases (32.7%) with spatial distribution symmetry and 37 cases (67.3%) with spatial distribution asymmetry. Those indexes of benign lesions and malignant nodules were different (P<0.05). There were differences of SEN, SPE, PPV, NPV and ACC between 3DCPA and TIRADS (P<0.05). The sensitivity and accuracy of combined 3DCPA and TIRADS was obviously higher than that of the single method. Conclusion Blood flow distribution in 3DCPA, vascular contorts, spatial distribution is meaningful for the diagnosis of benign and malignant thyroid nodule. The vascular contorts the sensitivity and specialty degree is high. TIRADS standard of thyroid nodule plays the role of standardization, and canonical in Ultrasonic description, provides a risk evaluation of thyroid nodule. The combination of 3DCPA and TIRADS can improve the sensitivity and accuracy of diagnosis and reduce the misdiagnose．