Esophageal obstruction as a result of persistence of the right aortic arch was diagnosed in a 3-month-old male Persian cat. Regurgitation right after weaning and retardation were noted in this cat. Survey radiographic signs on the lateral view include ventral deviation of the thoracic trachea caused by draping of the dilated esophagus over the dorsum of the trachea and a distinct interface of the dorsal wall of the esophagus silhouetting with the cranial thoracic hypaxial muscles. On the ventrodorsal view, the cranial mediastinum was widened with soft tissue density. The trachea was deviated to the right. In an esophagram, the segmental dilation of the esophagus with constriction of the lumen just cranial to the heart base was apparent. Thoracotomy was performed and corrective surgery was carried out. At surgery, it was confirmed that the esophagus was constricted at the cranial to the base of the heart.