This paper analyses preference erosion effects on the agricultural sector of the EU’s Mediterranean Partner Countries (MPCs) with the partial equilibrium multi-commodity multi-region world trade model AGRISIM. Supposing that the preferences to the MPCs granted by the EU remain as of 2001 then the effects are evident for high protected markets like beef in Turkey, milk and rice in Morocco and olive oil in the MPCs. Supposing a free trade area between the EU and the MPCs, then the impacts are high for beef, milk and sugar. The farmers’ income decreases, but the consumers and the taxpayers benefit from lower prices and the overall welfare in all MPCs increases.