Pollen tube growth and double fertilization have profound effects on seed production.Bamboo plants usually have a relatively long vegetative growth,so it is not easy to have the opportunities to study their reproductive characteristics.In this article,characteristics of pollen tube growth and double fertilization in the florets of Arundinaria simonii f.heterophylla were investigated.The main results are shown as follows:(1)30 minutes after pollination,almost all pollens of A.simonii f.heterophylla germinated on the stigma;(2)pollen tubes entered style in 1-2 h;(3)5 hours after pollination,a lot of pollen tubes bundles formed and a few pollen tubes grew along the intercellular spaces in the pistil;(4)8 hours after pollination,pollen tubes entered micropyle;(5)15-18 hours after pollination,two sperm nuclei fused with egg nucleus and polar nucleus separately,forming the zygote and the primary endosperm nuclei separately;(6)20-30 h after pollination,most pollen tubes were still observed in the pistil;(7)2 days after pollination,pollen tubes disintegrated and most of the pollen grains died.The time for sperms to reach the micropyle from the stigma is about 8 hours.