Abstract: This paper deals with the development of embryo sac and the parthenocarpy of Zizyphus jujuba Mill. The results are as follows: In Ningxia round jujuba, there are one to four archesporial cells but ordinarily only one of them can develop to megaspore.mother cell and the others degenerated. The embryo sac belongs to Allium type. Two megaspore nuclei take part in the formation of female gametophyte. The development of fruits doesn't depent on the fertilization. So the Ningxia round jujuba is a stable parthenocarpy. The relation between the development of fruits and the pollination was discussed.

Key words: Zizyphus jujuba Mill., Allium type, Parthenocarpy