We reported a rare case of perforation of the piriform sinus caused by gastroenterological endoscopy examination, leding to deep cervical abscess. The patient was a 56-year-old man who complained of dyspnea, high-grade fever and neck pain after gastroenterological endoscopy examination. Computed tomography revealed a deep cervical abscess and obstruction of the airway. We immediately, performed drain-age under general anesthesia, and found a perforation at the piriform sinus. He was treated with frequent wound washing and the daily intravenously instillation of antibiotics for anaerobic bacteria, and was discharged 31 days after the operation. Early diagnosis and operation are important for the management of deep cervical abscess.