Histoplasmosis is a deep mycosis with a high prevalence in America. Its aetiological agent, Histoplasma capsulatum, is found in Mexico, mainly in confined spaces, where it grows on bat guano or bird droppings. A research project has been developed in the State of Guerrero, Mexico, where many contaminated caves and mines are visited by individuals and epidemic outbreaks have been recorded. Data concerning human skin test response to histoplasmin antigen, host genetic predisposition to Histoplasma infection, sociocultural, socioeconomical and ethnobiological aspects of the disease in Guerrero are summarized in this paper.