A 39-year-old man from Argentina, who had come to Japan 13 years previously, had been suffering from oral pain for several months. He was biopsied twice and treated with oral predonisolone without improvement. A number of white granular lesions with erosions were observed on the hard palate and buccal mucosa. Histopathological examination revealed a well-demarcated abscess with an accumulation of neutrophils, surrounded by epithelioid cell granulomas. Round eosinophilic bodies, considered to be fungal elements, positive for PAS and Grocott staining, were observed. Chest CT revealed cavities in the lung. A white yeast-like colony was cultured from bronchial lavage fluid and Paracoccidioides brasiliensis was identified. The patient was treated with liposomal amphotericin B followed by oral itraconazole 400 mg/day, with a favorable clinical course. Paracoccidioidomycosis, an imported mycosis, is rare in Japan and sometimes causes difficulty in diagnosis, resulting in inappropriate treatment.