Abstract The objectives of this study were to assess aflatoxin M₁ (AFM₁) contamination in cow and goat milk and whey samples collected from small dairy producers in rural areas of Zlatibor. The study involved a total of 60 samples of cow milk (n=15), cow whey (n=15), goat milk (n=15) and goat whey (n=15). In order to elucidate the distribution and stability of AFM₁ during milk processing, cheese manufacturing trials were performed using cow milk naturally contaminated with different concentrations of AFM₁ (<0.05 to >0.25μg kg⁻¹). AFM₁ concentrations were measured using a validated immunoassay method (ELISA). None of the samples of milk or whey collected from areas of Zlatibor were contaminated with AFM₁. Contrary to that, in all of the analysed samples of whey obtained from contaminated cow milk, AFM₁ was detected. We conclude that whey contains 40-60% of the amount of AFM₁ present in milk. The results obtained indicate the intensification of dairy production and the supplementation with commercial feed such as maize could be risk factors that impact on the AFM₁ incidence in contaminated milk. In addition, our study demonstrates there is a potential health risk due to the consumption of whey obtained from contaminated milk.