In vitro cultures of five moss species were established on hormone-free MS medium, or on MS medium supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid and kinetin. In vitro culture of Eurhynchium praelongum (Hedw.) B., S. & G., has been initiated from the apical shoots of the gametophytes, and the cultures of Aloina aloides (K.F.Schultz) Kindb. Brachythecium velutinum (Hedw.) B., S. & G., Ceratodon purpureus (Hedw.) Brid. and Grimmia pulvinata (Hedw.) Sm. were initiated from the spores of immature sporophytes. In secondary protonema culture of Eurhynchium praelongum, spontaneous regeneration occurred successfully. Protonema cultures of Aloina aloides, Brachythecium velutinum and Ceratodon purpureus reversed to caulonema culture where bud formation occurred. Grimmia pulvinata cultures remained at the protonema stage. Aloina aloides (K.F.Schultz) Kindb., Brachythecium velutinum (Hedw.) B.S. & G., Ceratodon purpureus (Hedw.) Brid., Eurhynchium praelongum (Hedw.) B.S. & G. ve Grimmia pulvinata (Hedw.) Sm. Yosunlarinin ‹n vitro Kulturu Ozet: Hormonsuz veya farkli konsantrasyonlarda oksin ve sitokinin iceren besi ortamlarinda (MS) yaflamlari tehlikede olmayan cok sayidaki yosun turu icin in vitro kulturleri oluflturulmufltur. Eurhynchium praelongum (Hedw.) B.S. & G.'nin in vitro kulturune gametofitlerin uc surgunlerinden, Aloina aloides (K.F.Schultz) Kindb., Brachythecium velutinum (Hedw.) B.S. & G., Ceratodon purpureus (Hedw.) Brid. ve Grimmia pulvinata(Hedw.) Sm.'nin in vitro kulturlerine ise olgunlaflmamifl saprofitlerin sporlarindan alinarak bafllanmifltir. Eurhynchium praelongum'nin sekonder protonema kulturu do?al olarak baflarili bir flekilde oluflmaktadir. Aloina aloides, Brachythecium velutinum ve Ceratodon purpureus'nin protonema kulturleri tomurcuk formasyonunun gerceklefltii kaulonema kulturune donuflmufl, Grimmia pulvinata ise protonema evresinde kalmifltir. Anahtar Sozcukler: Yosunlar, in vitro kulturu, Aloina aloides, Brachythecium velutinum, Ceratodon purpureus, Eurhynchium praelongum, Grimmia pulvinata