Abstract:Eucommia ulmoides Oliv cultivated at Xi‘an pollinates in the middle of April, and fertilizes in the end of April. The zygote is dormancy about 35 days long, and then divides. Proembryo is formed in the beginning of June, its differentiation development is in june till july, and maturation it about August till October.The volume of zygote increased by 1—1.5 times in the dormancy stage, the polarity became obvious. After twice transverse division, the zygote formed L, L‘, M, CI proembryo in a linear arrangement. Then L, L‘, M divided in no strict rule. When the whole embryonic cell reached 8—10 rows, the division of the cell from L, L‘ proceeded in tangential surface, the division of 1—2 layers upon the cells from M and CI proceeded in vertical. Since the end of chalaza had 5 rows of cell, all of them had inner and outer layers, formed embryonic body with short bar shape. The end of micropyle had cells of 7—9 single row formed suspensor. When the embryo was differentiation and development, the derivative of terminal cell formed in cotyledon, plumule, and the middle and upper part of embryonal axis. The embryonal cell source of the basal cell formed in the middle and lower part of embryonal axis, and radicle, root cap. The development of embryo of Eucommia ulmoides Oliv belongs to chenopodiad type.