Aflatoxins are considered a potential hazard to public health, due to their toxicity and carcinogenicity. Under favorable environmental conditions, insect attack, and substrate, aflatoxin-producing fungal species can grow in certain foods and feeds. The total aflatoxin distribution due to environmental conditions (temperature, relative humidity, and rainfall), collection phase (early, middle, and late), microbiological analysis of aflatoxin-producing strains, and nutrients (minerals, moisture, and carbohydrates) was evaluated in samples of corn grown in Costa Rica. A multiple regression analysis design determined that total aflatoxin levels were significantly correlated (p≤0.05) with the presence of AspergiIIus flavus in the grain and temperature conditions