The flotation of niobite, fersmite, and ilmenorutile was studied using 3 collectors with various concentration and pulp pH. The collecting property of different representative collectors was investigated. Experimental results show that diphosphonic acid is an effective collector for valuable niobium-containing minerals. A flotation recovery of 90.87%-91.7% is obtained with 75 mg/L di-phosphonic acid at pH 2-4. The chemical adsorption of diphosphonic acid on these 3 minerals surface might lead to the high recov-ery efficiency of the minerals, which is proved by IR and X-ray photoelectron spectroscopy spectra.