In a two factor field experiment, the yielding level and economic efficiency were studied of oats cultivated using pure sowing stands and mixed stands of oats, spring barley, and spring triticale. The cereals studied were cultivated using an organic and a conventional farming system. Based on the research accomplished, it was found that the achieved yielding levels of oats and its mixtures with other cereals cultivated using the organic system were by 12% lower compared to the conventional farming system. The crop yield of oats cultivated in pure sowing stands was lower than the crop yield obtained from the mixed oats and spring barley stands. The direct costs of tillage were almost 5 times lower when the use of artificial fertilizers and pesticides was abandoned. Despite the lower production value gained from the organic system, the personal income obtained from this farming system was, on average, 4 times higher than the personal income from the conventional farming system.