We report a case of pneumonitis induced by PL granules. A 45-year-old man took PL granules and other drugs for fever and headache. Because he subsequently developed high grade fever, cough and diarrhea, he was admitted to our hospital. His chest X-ray film revealed multiple patchy shadows in both lung fields. Analysis of bronchoalveolar lavage fluid (BALF) disclosed a high number of cells (total), lymphocytes, and a high CD4/CD8 ratio. Microscopic examination of transbronchial lung biopsy (TBLB) specimens showed infiltration of mononuclear cells and thickening of the alveolar wall. After discontinuation of drugs, his condition (symptoms, laboratory data, and chest X-ray findings) promptly improved. Lymphocyte stimulation tests (LST) for PL granules and acetaminophen were positive and an oral challenge test with PL granules was also positive. Based on these findings, we diagnosed this as a case of pneumonitis and enteritis due to PL granules. To our knowledge, this is the first reported case of pneumonitis due to PL granules.