Formation of two diametrically opposed schools of agrarian economics in theory and practice is studied. The first one believes that agriculture is subject to the general economic laws of the capitalist economic system (A. Smith, D. Ricardo, K. Marx), while the second one believes that the branch has features that limit this subordination, with the result that this area only “reflects” the general capitalist political economy. The author reveals the foundations of schools of the second direction formed by the classics of agroeconomics (A. Thaer, J. von Th?nen, T. Brinkmann) and further developed by E. David, S. Bulgakov, T. von der Goltz, O. Chayanov, M. Makarov and other scientists. According to the review of economic practices in the global agrarian space, it is proven that agriculture is successfully developing where specificity of socio-economic relations in the agricultural sector is confirmed. The specificity in this area is caused by interweaving the natural and economic principles of reproduction, peculiarities of the use of material, technical, labor and land resources, influence of the rent factor, low elasticity of demand for the main types of agricultural products and foodstuffs and significancy of social and ecological functions of agriculture for the development of society. Countries where agrarian policy is based on the principles of the general economic laws of capitalism that argue the advantages of large capitalist farms, the concentration and deep specialization of agriculture, the subordination of the production to profit maximization, etc., face negative social and economic consequences. The losses from these consequences collectively outweigh the economic benefits of a capital-only management system. The development of agroeconomic science under conditions of modern scientific and technological progress and globalization processes is analyzed. The agroeconomic science, expanding the substantial content of social and ecological functions of agriculture under influence of positive results and negative consequences of these processes, proved the equivalence of these functions to the economic function of the industry. The essence of the concept of multifunctionality of agriculture, which is acknowledged by the international community as an instrument for developing agrarian policies for sustainable agriculture development, is revealed. In this context, the problems of domestic scientific agroeconomic trends and the consequences of their implementation in the process of reforming the agrarian sector of Ukraine are analyzed.