Harmful effects of fungi have been known for a long time. They can directly affect the health of humans and animals as parasites, causing disease known as mycosis. However, some types of mold in certain conditions are harmful to human and animal by forming toxins as the product of their metabolism. Such toxic substances are called mycotoxins, and disease caused by them is called mycotoxicosis. Mycotoxicosises are therefore alimentary poisoning products of toxic mold – mycotoxins, for humans and animals. Most of the molds that cause spoilage are generally aerobes. Molds of the genus Aspergillus, Fusarium and Penicillium produce mycotoxins (aflatoxin, ochratoxin, trichothecenes, zearalenone and citrinin, ergotamine, fumonisin and patulin), which have been connecting to the cause of many chronic diseases (cancer of the liver, uterus and esophagus, various ataxia and tremorgenic, allergies and asthma). The distribution of mold is very wide (food products - meat, fruits, vegetables, cereals, bread, and also in the air), which are huge health and economic problems. Based on studies of mycotoxins, the governments of many developed countries reduce or completely prohibit the cultivation, importation and production of contaminated products in order to save the health and quality of life of people and animals.