The nitrogen fixed by blue-green algae could supply rice plants with their needs of nitrogen. Cyanobacteria can fix atmospheric nitrogen in submerged rice fields.  A field experiment was carried out at Rice Research and Training Center, Sakha Research Station, Agricultural Research Center ( ARC ) Kafer EL-Sheikh, Egypt during the summer season 2016 to investigate the effect of  biofertilizers as inoculants (Anabaena oryzae D  and Nostoc muscorum K) . The both cyanobacterial strains were selected  according to the amount of indole acetic acid and nitrogenase activities. The results indicated that highly significant increase in plant height, panicle length, number of tillers/plant, number of panicles/plant, biomass and grain yield t/ha. On the other hand , there were no significant for 1000 grain weight and harvest index. The cyanobacteria have been saved the inorganic nitrogen application by 20-25% compare with recommended nitrogen application.