Abstract:Core leptosporangiatae is a major fern group in the Filicinae. The origin of the wall cell on archegonium has not been specifically reported yet. Combined with research on sexual organs of Cyatheaceae and other 10 more groups, this paper takes Dryopteris goeringiana (Kunze) Koidz. as an example, at the condition of artificial environment, observed the development of the archegonium by paraffin section method. The results show that: (1) the archegonium originates from an initial cell and a plurality of vegetative cells on the gametophyte; (2) Initial cell gives rise to a column of three cells by two unequal divisions, from outside to inside, there are neck wall cell, central cell and basal cell; (3) Central cell ultimately developed into an egg cell, ventral canal cell and neck canal cell;(4) Basal cell divided into 1-4 wall cells under the ventral wall of the archegonium; (5) The wall cells around the ventral of the archegonium are directly transformed from the vegetative cells adjacent to the egg cell. It is the first time to propose that the archegonium of the core leptosporangiatae is multicellular origin, the morphological basis is provided for the study of the evolution of sexual reproduction in the archegonium plants.