An indirect atomic absorption spectrophotometric method for the determination of 0.5-5 moles nitrate is described. The method is based on the formation of insoluble ternany complex, (Ag (Phen)2 )NO3, by adding an excess of (Ag(Phen)2)+solution in nitrate sample. Absorbance of unreacted silver ions has been measured in an air-acetylene flame. The effect of various ions has been investigated. The method is successfully employed for the determination of nitrate in fertilizer samples.