Abstract: There are many methods that have been reported for measuring NO₂^- at home and abroad in recent years. Such as ultraviolet luminosity, increasing sensitivity luminosity, polarography, ion chromatography, catalytic luminosity, catalytic potential, flow injection analysis luminosity, bakelite varnish resin sensor direct potential, etc. These methods have their each merits as well as their limitations and demerits. If we want to set up a perfect method system of measuring Nitrite, we should research from reaction mechanism, reaction conditions, elimination of interference ions, and so on.