Aflatoxin contamination of peanuts has been of worldwide concern since the 1960s. Aflatoxins are fungal secondary metabolites that have been associated with severe toxicological effects to human and animals, which can cause enormous economic loss to producers, handlers, processors and marketers of contaminated peanuts. Aflatoxin contamination of peanuts is unavoidable due to the varied factors in pre-harvest, harvesting, and post-harvest stages of peanuts. The review summarizes the factors influencing aflatoxin contamination in the whole supply chain of peanuts.