Mold is a type of fungus, which is characterized by a relatively developed mycelium and no large fruiting bodies. Like other fungi, they also have cell walls, parasitic or saprophytic means of survival. Some molds transform food into toxic substances, and some may produce toxins in foods, that is, mycotoxins. Since the discovery of aflatoxin, the contamination of food by mold and mycotoxins has attracted increasing attention. The harm to human health is huge, mainly manifested by chronic poisoning, carcinogenic, teratogenic and mutagenic effects.