The title of this Master’s thesis is Economy of Fast-Growing Tree Cultivation. The introductory parts of the thesis characterize the Energy Policy of the Slovak Republic and its objectives with respect to the possibilities of exploiting a biomass. Orientation of the energy policy on the support of renewable sources of energy may decisively support a targeted cultivation of fast-growing trees. The theoretical part of the Master’s thesis defines basic prerequisites and possibilities of planting fast-growing trees on agricultural and forest soil. On the basis of the theoretical starting points, the practical part of the thesis contains a financial and economic analysis of the project of cultivating fast-growing trees. To evaluate the economic effectiveness of the plantation, the EcoWillow 2.0 programme was used, which takes into account the activities and costs connected with the starting and operating of the plantation. The model project of a fast-growing tree plantation is prepared for a surface area of 19.8 hectares in the municipality of Mníšany. When the economic criteria were evaluated, the project proved to be profitable, with the invested capital recovered within 13 years.