The megasporogenesis,microsporogenesis and the development of female and male gametophyte of Nicotiana debneyi were studied by carbol fuchsin staining and paraffin sectioning.The results showed that:(1)N.debneyi is hermaphrodite flower and the microspore develops earlier than megaspore.(2)Microsporogenesis and development of male gametophyte of N.debneyi are normal but there are chromosome bridges,chromosome fragment,laggard chromosome in a few cells.The meiosis in microspore of N.debneyi is simultaneous cytokinesis and the tetards are decussate or tetrahedral types.The mature pollens belong to 2 cell type.(3)N.debneyi is ovary 2-locular,axile placenta,ovules numerous and polygonum type of mature embryo sac.Megasporogenesis and the development of female gametophyte of N.debneyi are normal.