Assessment of the sustainability of nutrient balances in selected group of 20 organic farms located in the Kujawsko-Pomorskie was aim of the research. Balance of NPK, the share of green fields and the balance of soil organic matter were taken into account in the assessment. MACROBIL program was used to calculate the field balance. Organic farms were characterized by a positive, safe balance of nitrogen of 2.8 N ha-1 year-1. While the balance of phosphorus and potassium was negative and amounted, respectively, -2 and -21.6 N ha-1 year-1. Sustainable balance of potassium was noted in the animal farms, while strongly negative in farms specialized in plant production. Balance of soil organic matter in the organic farms was positive and amounted on an average of 0.53 t DM/ha. The highest values of this index were recorded in farms specialized in animal production. The share of green fields in the studied group of organic farms amounted slightly more than 50%, which indicates their great potential in reducing the negative effects associated with agricultural production.