[en] A new analytical form for non-extraction photometric determination of Ta microamounts in the presence of niobium is obtained. For the purpose Ta interaction with salicylfluorone (2-hydroxyphenylfluorone, SF) in citratesulphuric acid mediUm in the presence of surfactants is studied. Formation conditions and spectrophotometric characteristics of Ta complex with SF in the presence of gelatin, cetylpyridinium, syntanol and triton, X-100 are presented. It is established that in the system with syntanol H₂O₂ introduction results in efficient disguising of niobium, which is more considerable in acid medium (pH 1.3-1.5). When H₂SO₄ content is 0.4-0.5 mol/l, sodium citrate - 1.2-1.6%, H₂O₂ - 0.01-0.02%, syntanol (triton X-100) and 0.01-0.02% H₂O₂ up to 5 mg of niobium do not interfere with the determination of 1-5 μg Ta. In the process of tantalum determination the presence of 1-2 mg of Zr, Hf, Al is admissible. Interfering effect of 30 μg of Sn(4) and 50 μg of Ti (4) can be eliminated by means of introduction of 1x10^-2 M EDTA into solution. Techniques of tantalum, impurities determination in metal Nb and Nb₂O₅ are developed