Abstract: The samples of pure niobium and niobium products were completely transformed into niobium pentoxide, according to a certain proportion of mixed with the carrier, DC arc anode excitation, echelle grating and prism dispersion system of light.Selected characteristic spectral lines was received by the L-PAD signal detector, signal conversion and data processing were made by computer.For the determination of niobium oxide in elements Hf, DC arc plasma atomic emission spectrometry was used.The linear range is 10—200 μg/g, the method is simple, good precision and accuracy.