Abstract: The study of niobium-tartaric acid complex anion electrode based on trloctylhexadecylammonium site have been described. Electrodes prepared from dinenylphthalate shows the best performance characteristics and has been studied in more detail. The Nernstian response range of the electrode is from 10^-2 down to 5.0 × 10^-6M, the detection limit being 3.5×10^-6M. They are found satisfactory in the lifetime, response time, selectivity and stability. The proposed electrode has been testified by determining niobium concentration of mineral.