Blastomycosis dermatitidis, also known as North American blastomycosis, is a chronic suppurative, granulomatous lesion mainly in the lungs, skin and bones caused by Blastomycosis dermatitidis. The disease is mainly prevalent in North America, with a few sporadic cases in the United Kingdom and Mexico, but patients have a history of living in the United States or being exposed to contaminants of this bacterium. In my country, Wu Shaoxi et al. found a case of skin infection in a Chinese American in the United States in 1989, and Guo Runshen et al. reported this disease in 1999, which was a local infection. The disease is common in men aged 40 to 60. After the spores enter the alveoli, they are phagocytosed by macrophages, causing an inflammatory response including polymorphonuclear leukocyte infiltration, and then forming granulomas, which can all manifest as suppurative or suppurative granulomatous lesions. The clinical manifestations are primary pulmonary dermatitis blastomycosis, cutaneous dermatitis blastomycosis, and disseminated dermatitis blastomycosis. Fungal examination and lung examination are combined to help confirm the diagnosis. Amphotericin B is an effective treatment for blastomycosis.