Abstract: Polarity of megasporocyte in Ginkgo biloba took place before the initiation of meiosis. At first the nucleus of megasporocyte moved from the central portion to the micropyle end and later a vacuole appeared at the chalazal end and existed throughout the process of meiosis. The meiotic divisions of the megasporocyte were unequal and nonsynchoronous. The megaspore tetrads were mostly linearly arranged but sometimes T-shaped. T-shaped tetrads were apparently a result from an inclined division of a dyad cell which faced toward the micropyle end. A sequencial difference in the cell size of the tetrad, i. e. the largest at the chalazal end to the smallest at the micropyle end could be seen at its early developmental stage.

Key words: Ginkgo biloba, Megasporocyte, Megaspore formation