Achalasia cardia is an esophageal myenteric plexus disorder characterized by absence of or incomplete lower esophageal sphincter relaxation and esophageal aperistalsis; Heller’s myotomy is the main treatment of choice due to a lower failure rate. Recently, peroral endoscopic myotomy (POEM) has been reported as an alternative treatment for achalasia due to persistent symptoms after Heller’s myotomy. An Indian male, aged 18 years, was admitted to the hospital due to dysphagia which had started more than 3 years ago. He also complained of occasional regurgitation and retrosternal pain with Eckardt score 6. Heller’s myotomy was performed 2 years ago. Barium swallow showed achalasia cardia and upper gastrointestinal endoscopy found liquid residue and resistance at the gastroesophageal junction. Esophageal manometry is concluded as achalasia cardia type II with a median integrated relaxation pressure (IRP) of 25.6 mm Hg. He underwent POEM; with the help of a submucosal tunnel, an extension of up to 1 cm beyond the gastroesophageal junction could be achieved with a posterior orientation of myotomy. There were no adverse events after the POEM procedure. He was treated with a soft diet for 10 days and other supportive treatments. Following POEM, barium swallow showed a significant improvement and esophageal manometry exhibited that the basal lower esophageal sphincter pressure was normal with complete relaxation on swallowing and normal median IRP. The post-procedure Eckardt score was 0. We reported an achalasia patient who received POEM after unsuccessful Heller’s myotomy and showed clinical improvement.