An 81-year-old man was admitted to our hospital due to persistent fever and dyspnea with pulmonary infiltrates. He was treated successfully by discontinuing his current medications, including Sai-rei-to, and administering glucocorticoids. Drug lymphocyte stimulation tests showed a positive result for Sai-rei-to alone, and the resumption of other regular drugs did not re-induce the lung injury. Therefore, we diagnosed the patient with Sai-rei-to-induced lung injury. Sai-rei-to is a combination drug that consists of Sho-saiko-to and Gorei-san. This paper briefly reviews drug-induced lung injury caused by Sai-rei-to or its components with a case report.