Aspiration can generate postoperative pulmonary morbidity of varing severity, depending on the type and volume of the aspirate. Epidural anesthesia can lead to local anesthetic systemic toxicity with mental change, followed by respiratory depression and abdominal and intercostal muscle weakness depressing the ability of the patient to cough and clear the airway. The authors experienced a case of pulmonary aspiration with systemic toxicity after epidural anesthesia for cesarean section. The chest X-ray showed alveolar consolidation at left lower lung field and arterial blood gases showed that PaO2 decreased. The exact causes of mental change and respiratory depression were unknown, but we suspected it lidocaine induced systemic toxicity due to vascular absorption, When airway reflexes are ineffective during face mask ventilation of the lungs, aspiration of clear oral secretions can generate small airway obstruction.