Occurrence of land rents in modern agriculture of the EU is confirmed by the long-lasting upward trend in agricultural land prices. However, a question arises whether these rents are differential ones, linked with a different productivity of agricultural land, absolute ones in the classical sense, or political rents in the meaning of the public choice theory? The objectives of the article are mainly theoretical. The authors made an attempt at verifying the concept of land rent formulated on the basis of studies carried out in Poland. This time, the scope of research includes a cross-section of all agricultural structures of the EU. According to the above-mentioned concept, the source of a modern land rent is higher expected productivity of capital in agriculture than in its market environment. This phenomenon is often justified by paying political rents within the CAP. Is it really the case? The conducted research answers i.a. the question: in which countries and agricultural structures the possible difference of the abovementioned capital productivity is the biggest and to what extent it results from political rents or other factors?