In the present work, the occurrence of the aflatoxins B and G, as well as a possible correlation between both were studied in 44 samples of peanut flour from 6 oil mills of the region Sorocabana, in the State of São Paulo. The samples were obtained in four collections representing material from two crops in two different seasons: March and May, in the rainy season and July and September, in the dry season. From the results it was concluded that: a) the occurrence of aflatoxin was generalized in that region, for all the samples were toxic; b) the toxicity level was found to be very high (figures from 0.1 to 10.0 ppm) being higher in the rainy season - average of 3.78 ppm, agains 1.74 ppm in the dry season; c) it was considered that only 4.54% of the material examined could be utilized for admixture in feedstuffs; d) it was not found correlation in the production of the aflatoxins B and G.