A survey of aflatoxin contamination in selected Colombian foods was conducted over a 12-month period on a total of 248 samples. Samples were collected in supermarkets, retail stores and stock centres and were grouped into five categories: (1) corn and corn products, (2) cereal grains, (3) rice and rice products, (4) legume seeds; and (5) snacks and breakfast cereals. Aflatoxins were identified and quantitated using a liquid chromatographic technique with a limit of detection of 1 ng/g for each aflatoxin. Aflatoxins were detected in 14 of 109 samples of corn and corn products, 4 of 40 samples of rice and rice products, 2 of 30 samples of legume seeds, and 2 of 11 samples of snacks and breakfast cereals. None of the cereal grains samples analysed contained detectable levels of aflatoxins. Twelve of the total of 22 positive samples exceeded the maximum tolerable level of aflatoxin B1 adopted in most countries (5 ng/g); 10 of these 12 samples corresponded to corn and corn products. The results of the present study indicate that aflatoxin B1 contamination in certain foods in Colombia is a major public health concern. Continuous monitoring of aflatoxin B1 levels in Colombian foods is advised.