There are no previous reports of esophageal perforation due to endoscopic submucosal dissection developing into pyothorax. We herein describe a case of esophageal healing following perforation in a 60-year-old woman undergoing esophageal endoscopic submucosal dissection. Post-procedural computed tomography revealed pyothorax in the right thoracic cavity, compressing the right lung. The pyothorax did not improve despite treatment with thoracic drainage because the esophageal lumen was connected to the right thoracic cavity. In order to close the site of esophageal perforation, we inserted a covered self-expandable metal stent. The affected site subsequently healed without complications, allowing the drainage tube and stent to be removed.