The paper analyses the legal regulation of the cultivation of fast-growing trees on agricultural land in Slovakia and Czechia. The focus is on the differences in the legislation of the two countries, the application of the regulations of cultivation of fast-growing trees in practice, the level of protection of agricultural land, and the support system for the cultivation of fast-growing trees. Comparison of national legislation dealing with the issue of planting fast-growing trees, taking into consideration the protection of agricultural land and the legislation on granting the state support has also been investigated in the context of European legislation. The procedure before the start of planting, the permission conditions for planting of fast-growing trees, the conditions and the process of support provision have been studied. The result of the documents analysis is a comprehensive comparative overview of the above-mentioned areas of legislation on the cultivation of fast-growing trees in Slovakia and Czechia and the identification of differences, benefits and practical impacts on the cultivation of fast-growing trees.