Abstract:Embryological features of threatened Orchidamha chinersis were studied with the help of a Ileitz microscope．Living specimens were collected from the South China Botanic Garden at Guangzhou．Special emphasis is given to the 0vule development, megasporogenesis, egagametogenesis and the development of endosperm The ovules of 0.chinensis are anatropous, crassinucellate and bitegmic．Micropyle is formed by inner and outer integuments Aril originates from top end of outer integumem．The ovule has a layer of parietal cells at the sporogcnous stage Sporogenous cell develops into a megaspore mother cell, and then divides meiotieally into a linear megaspore tetrad mad sometimes triad．Chalazal megaspore is functional. The development of the embryo sac is of Polygonum type．Chalazal end of mature embryo sac is narrow and elongated．The ovule has epistase and hypostase structures．Antipodal cells are longevous. The type of vascular bundle in the ovule belongs to postchalazal multibundles．The development of endosperm is of nuclear type．Plumule and radicle are not differentiated when the seeds fall. We recognize that the elongated part of the ovary, in Lowiaeeae is functional for continuous dovelopment of pollen．Main characteristic differences among 8 families in Zingiberales，and the reproductive biology of Lowiaceae are discussed．