Abstarct: A rapid, simple and accurate spectrophotometric method is proposed for the determination of nitrite.The method is baxsed on nitrite catalytic effect on the reaction of 2-(5-Bromo-2-pyridilazo)- 5- diethylamino phenol (Br-PADAP) and bromate in acidic medium and make it colorless. The reaction was monitored spectrophotometrically at 466 nm. Under the optimum conditions, nitrite could be determined in the concentration range of 0.020-0.36micro-g/ml. The detection limit of the method is 0.018 µg ml-1 for nitrite. The relative standard deviations for 6 replicated determinations of 0.060, 0.100, 0.150 micro-g/ml nitrite are 6.6%, 6.1% 3.3%. Interferences due to foreign ions are studied and the method is applied for the determination of nitrite in water and food samples. For determination of nitrite and nitrate in sample, nitrite is determined baxsed on catalytic effect on the reaction of PADAP and BrO3- in acidic medium. Nitrate is determined after reduction it into nitrite by cadmium- mercerized redactor. Under the optimum conditions, nitrate could be determined in the concentration range of 0 0.040-0.44 micro-g/ml. The detection limit of the method is 0.032micro-g/ml. The relative standard deviations for 6 replicated determinations of 0.050, 0.20 and 0.30 micro-g/ml nitrate are 8.6%, 4.0% and 2.7%, respectively. The method was applied to the determination of nitrite and nitrate in tab water samples