Esophageal achalasia is a disorder of the lower esophageal sphincter muscle. Our patient, a Japanese male in his 80's, had been experiencing dysphagia for almost 60 years. He was treated with balloon dilations and Heller-Dor 5 years prior to his present admission. Esophagogastroduodenoscopy, esophageal radiography, and high-myotomy manometry indicated that the symptoms were likely due to abnormal peristalsis. With the patient’s informed consent, we performed a peroral endoscopic myotomy（POEM）. The patient was discharged 4 days post-surgery. At the 6-month postoperative examination, no worsening of symptoms or relapse was observed. POEM is an excellent treatment method for esophageal achalasia from the perspective of therapeutic effect. We recommend that POEM be considered as the first-choice treatment for abnormal peristalsis after a Heller-Dor myotomy.