We encountered a patient in whom Bofu-tsusho-san (Chinese herbal drug) had induced pneumonitis. A 65-year-old man was admitted to our hospital because of cough, fever, and dyspnea about one month after treatment with Bofu-tsusho-san. BALF showed an increase in the total cell number and the percentage of lymphocytes. TBLB revealed interstitial pneumonia. The patient recovered after discontinuation of Bofu-tsusho-san alone. We diagnosed Bofu-tsusho-san-induced pneumonitis. Clinicians should be aware of drug-induced pneumonitis in patients receiving herbal drugs.