Purpose. Estimate phenological and morphological characteristics of Miscanthus giganteus J. M. Greef & Deuter ex Hodkinson & Renvoize, M. sacchariflorus (Maxim) Benth. and M. sinensis Anderss., obtained in vitro, and M. giganteus, propagated by rhizomimes (ex vitro) to attract them to the breeding process and create new forms of miscanthus for use in bioenergy. Methods. Seeds of M. sinensis, as well as M. sacchariflorus (2n), M. sacchariflorus (4n), introduced into culture and propagated in vitro according to commonly used methods (M. D. Melnychuk, A. Plazek et al.) were used in the studies. Phenological observations were carried out according to the methods of V. V. Zinchenko, M. V. Roik, D. B. Rakh­metov, and others. Statistical processing of the obtained data was carried out according to M. A. Shelamov and ot­hers. Results. M. sacchariflorus (2n) in the conditions of the Forest-Steppe of Ukraine does not enter into the flowering phase, whereas in M. sacchariflorus (4n) the flowering phase begins a month earlier than M. sinensis, which is an obstacle for transpollination of these species in the natural environment. M. giganteus, reproduced by rhizomes, in overwhelming majority of indicators (stem height and diameter, number of interstices and leaves, leaf area, length and width of cluster) dominate all species of mescanthus obtained in vitro. But the number of stems in the bush of M. sinensis is the highest (63 pcs.) and is almost 2–4 times higher than those of M. giganteus, obtained from risomes and in vitro. It has been revealed that the most promising forms for bioenergy use are M. sinensis, whose productivity is about 7 kg/m2 of green mass and M. giganteus, propagated by rhizomimes (ex vitro), where the mass of the aerial part is almost 9 kg/m2. But M. sacchariflorus (2n) and M. sacchariflorus (4n) should not be considered as promising species for use in bioenergy purposes, because their performance is very low compared to other species and is only 0.25 and 2.05 kg above ground mass from 1 m2. Conclusions. On the basis of the obtained data, the most promising forms of Miscanthus were established to attract them into the breeding process and to obtain new varieties with high biomass productivity for the needs of bioenergy.