Histoplasmosis is a fungal infection caused by the dimorphic fungus Histoplasma capsulatum. It is classically considered an endemic mycosis, even though the fungus has an opportunistic behavior in immunocompromised patients. People acquired the infection through the inhalation of conidial forms present in the environmental, such as caves dwelling bats and soils inhabited by chickens. The clinical features may vary from asymptomatic infections to disseminated severe forms that affect patients with acquired immunodeficiency syndrome or hematological malignancies and allograft recipients. The diagnosis is based on the detection of the fungus in organic fluids (sputum, blood, liquor) or tissues (histopathological assays), in the culture of biological samples and serological assays. The treatment of severe chronic respiratory acute or localized forms can be performed with oral azolic (itraconazol) and in the disseminated forms, the amphotericin B (preferentially the lipidic formulations) consists in the elected drug to initiate the therapy. Nowadays, histoplasmosis represents one of the most important systemic mycosis in the Americas, with broad distribution in all regions of Brazil.