Using the self-made Nano aluminum hydroxide as adjuvant,we immunized broilers with H5N1 vacine.As age increased,oil-adjuvant vaccine was absorbed,which left yellow traces.Nano adjuvant was absorbed quickly,and there were no yellow traces left.Alter 49 days,no inflammatory cells were observed in the nano adjuvant injected area except some around the blood capillarie.Inflammatory cells in the conventional aluminum group were also significantly reduced,while the oil group still had a lot of inflammatory cells observed in the injection area.Compared with oil adjuvant,nano adjuvant can reduce the side effects.