Abstract: In the self-incompatible line of Brassica oleracea L., with the aid of scanning electron microscope, we observed that the pollen grains failing to germinate in 18 hours after pollination would shrink and become small, finally up to shrivel. Other pollen grains germinate from its bourgeon channel, the rest bourgeon channels become shrink. Some pollen tubes twist failing to penetrate stigma papilla cells. Only a few pollen tubes can grow into the styles. With 5%NaCl solution treatment is studied, the surface papilla cells of the stigma tended to crimple or break. So most of the pollen grains are able to germinate and the pollen tubes could elongate into the styles to fecundation.