Abstract: A 2-month-old male Labrador retriever was treated for cough. Physical examination showed that the dogs were malnourished. The results of chest X-ray and esophageal barium meal showed dilation of the cephalic esophagus at the base of the heart and stricture of the esophagus at the base of the heart. Esophageal endoscopy revealed a large amount of grit and food debris in the esophageal diverticulum. The endoscopic probe could not pass through the stenosis. Combining medical history, physical examination, imaging examination and esophageal endoscopy to suspect abnormal vascular ring and secondary esophageal diverticulum, surgical treatment was decided. The left 4 th and 5 th intercostal thoracotomy was performed, and the persistent right aortic arch with left ductus arteriosus was detected. It could be seen that the ductus arteriosus ligament connecting the aortic arch and the pulmonary artery caused esophagus stenosis, and the remaining ligamentum arteriosus was ligated and cut to relieve the esophageal stenosis. After the operation, the dog stood to eat wet food for a long time, and no reflux or other abnormality occurred again. The dog was a typical case of persistent right aortic arch with left ductus arteriosus, and its diagnosis and treatment process suggested that animals with persistent right aortic arch usually required early surgical intervention. The prognosis of the case was influenced by the treatment effect of secondary macroesophagus and aspiration pneumonia post abnormal vascular ring.