Reexpansion pulmonary edema following pneumothorax, atelectasis, massive pleural effusion are clinically uncommon, but sometimes life threatening progression. Reexpansion pulmonary edema is usually ipsilateral but rarely contralateral or both. Reexpansion pulmonary edema was occurred when chronically collapsed lung is rapidly reexpanded by evacuation of large amounts of air or fluid. The pathogenesis of the reexpansion pulmonary edema is unknown but is probably mutifactorial. The etiological factors of the reexpansion pulmonary edema are chronicity of the lung collapse, technique of the reexpansion, airway obstruction, loss of the surfactant, and pulmonary artery pressure changes. In the treatment of the chronically collapsed lung, physician must be remembered the possible events, and to prevent of the complication.