An epidemiological survey with histoplasmin skin test was performed in 392 poultry farmers and 265 workers considered without occupational risk of exposition to Histoplasma capsulatum, etiologic agent of histoplasmosis. The results were positive in 28.8% and 13.2% in both groups respectively. Statistically, there was a significant difference between the two groups, so it can be considered that poultry farmers are in occupational risk of infection with H. capsulatum. In the first group, the workers which are more closely related with chicken manure showed a higher reactivity to histoplasmin skin test. The working time in the farms seems to influence in the test reactivity too.