The leading cause of death of massive hemoptysis is the aspiration of blood into the contralateral normal lung resulting in asphyxia. The management of massive hemoptysis can be performed by the evacuation of the blood, and the protection and ventilation of the uninvolved lung from aspiration. Double-lumen endotracheal tubes provide lung isolation, the ability to ventilate one or both lungs, and suction in case of acute endobronchial hemorrhage. We report a case of blood aspiration and hypoxemia which occurred during one lung ventilation using single lumen endotracheal tube for left pneumonectomy. The patient was treated with a supplement of 100% oxygen, continual suctioning, and positive-pressure ventilation. If we had used a double-lumen endotrachal tube, it would have enabled us to separate both lungs, to clear the left lung, and to apply ventilatory support on the contralateral lung.