The aim of this study was to investigate the management and treatment for complications during and after peroral endoscopic myotomy (POEM) for patients suffering from esophageal achalasia (EA). The data of 119 cases of EA patients who underwent POEM from October 2010 to July 2011 and the complications that arose during the operation, after the operation, and during follow-up were analyzed. Complications that occurred during the operation included cutaneous emphysema (22.7 %, 27/119) and pneumothorax (2.5 %, 3/119). Postoperative complications included pneumothorax (25.2 %, 30/119), subcutaneous emphysema (55.5 %, 66/119), mediastinal emphysema (29.4 %, 35/119), delayed hemorrhage (0.8 %, 1/119), pleural effusion (48.7 %, 58/119), minor inflammation or segmental atelectasis of the lungs (49.6 %, 59/119), and gas under diaphragm or aeroperitoneum (39.5 %, 47/119). Complications that occurred during follow-up included one case of difficulty eating caused by the stricture of mucosa and one case of dehiscence at the mouth of the tunnel created during surgery, with food retention. No deaths occurred. All complications were resolved through traditional treatment. No additional surgery was needed. Complications arising during and after POEM should be treated quickly and can be resolved by using traditional treatment. POEM can be expected to become the preferred treatment for EA.