This paper presents the possible development scenario of the Polish agricultural sector till 2020. It also assesses the impact of macroeconomic growth, CAP reforms and worldwide policies towards the agriculture on this development. The scenario is build using an extended version of the Global Trade Analysis Project model GTAP which is a computable general equilibrium model of the world economy. The analysis shows that the growth of Polish agri-food sector observed after accession to the European Union will be prolonged in the future and will lead to an increase of agri- food sector incomes. However, it is expected that the positive trade balance in agri-food products will decrease significantly in consequence of the world trade liberalization and the EU policy stimulating biofuels production.