Grasses are considered as one of the most important sources in low-cost feed for for animals, but also a substrate for the production of renewable energy. We studied the quality of the freshly harvested biomass and hay of Romanian cultivars of tall fescue Festuca arundinacea: 'Adela', 'Brio', 'Măgurele 5', created at the Research and Development Institute for Grasslands, Braşov, Romania and cultivated in the experimental plot of the National Botanical Garden (Institute) "Alexandru Ciubotaru", Chisinau, Republic of Moldova. The samples for assessment were taken in the 2 nd year of growth, when the plants were cut for the 1 st time. The amount of dry matter (DM), crude protein (CP), crude ash (CA), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), cellulose (Cel), hemicellulose (HC), digestible dry matter (DDM), organic matter digestibility (OMD), relative feed value (RFV), the metabolizable energy (ME), the net energy for lactation (NEl), biomethane production potential (BMP) were analyzed. It has been determined that the green mass productivity of the tall fescue cultivars achieved 30.83-36.96 t/ha, the dry matter contained 114-136 g/kg CP, 74-89 g/kg CA,