Abstract: The gametophyte development of Blechnum orientale L.from China is observed under the condition of liquid medium in this paper.The results show that the spore of B.orientale is bilaterally symmetric,elliptic in polar view,semicircle or fabaceous in equatorial view,the lophate is formed by the perispore;The pattern of spore germination is of vittaria-type;the prothallial development is aspidium-type;The developed prothallial is cordiform.Through comparative analysis,it is feasible to make use of mixed soil to cultivate when the spores of fern develop.It is also feasible to use liquid medium in the study of the development of gametophyte.From of the view of spore morpha and gametophyte development,B.orientale is more evolutional species in fern,and close to dryopteridaceae in genetic relationship.The results try to provide some medium information for the culture of fern gametophyte and spore propagation,as well as accumulate some data for ferns systematic.