Abstract: The morphologic characters of pollen grain in two species ot Setaria have been observed by use of electron microscope. The result shows that the shape of pollen grains are round or approximately round. The surfaces of the pollen grain are rather rough, full of projection or starlike grains. Each pollen has an aperture and a lid on it. The characters which mentioned above are different between cultivated varieties and wild spcies. Therefore the aster grain on the inner wall of the pollen may be an important morphological index for identification of male sterillity.

Key words: Pollen grain, Starlike grains, Aperture, Lid on the apeiture