The nonrecurrent laryngeal nerve is a rare anomaly that may increase the risk of nerve injury during thyroid surgery. We experienced a case of nonrecurrent laryngeal nerve seen in a 35-year-old woman with adenomatous hyperplasia on her right thyroid. The nonrecurrent laryngeal nerve was incidentally found during the right thyroid lobectomy. It directly branched from the right vagus nerve and followed a transverse path parallel to the trunk of the inferior thyroid artery. The right lobectomy was performed with a careful preservation of the nerve. Postoperatively, the review of CT scan which was taken preoperatively revealed an aberrant right subclavian artery, which arose from the aortic arch and crossed behind the esophagus. To avoid an inadvertent injury to the nonrecurrent laryngeal nerve during thyroid surgery, it is important to be aware of the possibility of a nonrecurrent laryngeal nerve, particularly when an aberrant right subclavian artery is recognized preoperatively.