Abstract: Objective This paper analyzes the reason of the ultrasonic misdiagnosis of aortic arch and discusses the diagnostic thinking, methods and experience. Methods A retrospective analysis was performed on 5 cases of aortic arch isolated from preoperative ultrasonography or reexamination. Results The 5 cases of misdiagnosis were confirmed by surgery, angiography and double-source CT, of which 3 were type A, 2 cases B, and the sonogram had commonness, which was different from the combination of malformation.Two cases were combined with ventricular septal defect. One case of the main pulmonary artery septal defect and the right pulmonary artery anomaly originated from the ascending aorta, and one case of isolated aorticarch was broken. Conclusion Ultrasound examination, discovered that the ascending aorta and aortic arch drop small diameter developing, pulmonary artery significantly broadening, pulmonary hypertension and heart malformations don''t match, should be alert to the aortic arch is broken possible, carefully check the aortic arch.