Abstract: Experiments were carried out on the experiment farm of Anhui agricultural university with pool culture from 2004 to 2005. Effects of waterlogging at booting stage on N nutrition and yield were studied by applying simulation waterlogging method. The results showed that waterlogging at booting stage significantly influenced N nutrition Absorption content and reduced in dropping of total flag leaf chlorophyll content and net photosynthesis reducing and the grain weight and economic yield at last.