The vegetation of the Forràs and Istvàn caves at Lillafured in Hungary is composed of algae, micro- and macrofungi and mosses. The algae in both caves are represented by unicellular Cyanophyta and Chlorophyta with small species numbers. The macrofungi are Coprinus and Polyporacea spp. while it was impossible to identify the microfungi. The moss flora is richly developed and it can be supposed to represent a secondary vegetation at the artificially illuminated places of the caves. In Forràs cave 7, and in Istvàn cave 15 different mosses were found, only 3 of which proved to be common to both caves: Rhynchostegium murale, Eucladium verticillatum and Pohlia sp. A rare and interesting species: Fissidens minutulus occurred at several localities in Forràs cave.