Abstract:Gametophyte development of Egenolfia sinensis and E.bipinnatifida （Bolbitidaceae）were studied by the microscopy.The results indicate that both of them have similar features in spore germination and gametophyte development.The spores are bilateral,allmonolete.The spore germination pattern is the vittaria-type.The gametophyte development undergoes the filament and plate and finally forms the heart-shaped prothallus.Club-shaped,multicellular,marginal hairs are mostly found on the young prothallus towards the anterior end.The development of the prothallus is the drynaria-type.Sperms are produced in the young prothallus stage,while the archegonia are produced only in growing point under the large heart-shaped prothallus.Sex organs are the leptosporangiate-type.After fertilization,the zygotes develop into sporophyte.We discussed the phylogenetic relationship of Bolbitidacea,Dryopteridaceae and Lomariopsidaceae through comparisons of the gametophyte development.