Two batches of long-set cottage cheese were prepared from milk naturally contaminated with aflatoxin M1. Cottage cheese was stored for 2 weeks at 7°C. Analyses for pH, moisture content and AFM1 were done on days 0, 3, 7, 10 and 14 of storage. In comparison with the initial curd concentrations (18.3 and 20.5 μ of AFM1/kg of cheese for trials 1 and 2, respectively), AFM1 concentrations in the finished product did not decrease appreciably during storage. Overall average concentrations of AFM1 in trials 1 and 2 from day 0 to day 14 were 15.0 and 20.5 μg of AFM1/kg of cheese, respectively.