Barley (Hordeum vulgare L.) matures faster and more evenly under a hydroponic system than a conventional soil based system. Supplemented Azolla (Azolla Pinnata) to hydroponic system as an aquatic free floating fern provides protein with all essential amino acid which is required for animal nutrition. So, this investigation aimed to evaluate green fodder production and inhibition of root rot fungi under hydroponic conditions for barley. The experiment has been conducted under temperature and artificial illumination at growth room of Soilless Culture Laboratory, Sadat city University, Egypt. The results showed that green fodder can be produced in 8 days using hydroponic technique. Trays treated with Azolla gave more green fresh yield (11.8 kg/tray) than untreated ones (7.2 kg/tray). Adding Azolla increased of protein, N, P and K content percentages by 28.7, 0.98, 0.82 and 0.70 %, respectively, as compared to no addition of Azolla. There is no disease incidences were achieved with treated by Azolla as compared to 26.0 % with those untreated by Azolla. It could be concluded from this study that adding Azolla to hydroponic barley forage production improved green forage yield and its chemical analysis