The determination of the degree of contamination of cereals by moulds in organic farming conditions, with limited protection still requires explanation. Especially in the moist and warm, we can expect the occurrence of fusariosis of the ears. It is also important to identify other pathogenic fungi colonizing cereal grain crops in both farming systems. The aim of this study was to evaluate the quality of mycological cereal grains (barley, mixed cereal, oats, wheat, triticale, rye, spelt), grown in organic and conventional fields, harvested in 2010 in Kujawsko-Pomorskie province. In the samples collected from the organic farms the highest number of fungi was found in the samples of barley grains and the lowest in wheat and triticale, with the most numerous moulds of the genera: Aureobasidium, Penicillium, Cladosporium and Eurotium. Whereas in the samples collected from the conventional crops rye grain samples showed the highest and mixed cereals the lowest levels of moulds. Similarly to the organic harvest, the conventional ones contained mainly: Aureobasidium, Penicillium, Cladosporium and Alternaria. In case of Fusarium, a slightly higher number was found in cereals from organic farms, yet the highest percentage of contamination (in both farming systems) was identified in the mixed cereals.