Niobium ethoxides，directly prepared by electrochemical method using metal niobium as anode，were characterized by Raman spectra，FT-IR spectra and element analysis. The effect of conductive agents，residual moisture， current density，polar distance and electrolyte temperature on the synthesis were investigated by experiments. The technology were optimized as dewatered ethanol，(C2H5)4NBr concentration 0.04 mol/L，polar distance 2.5 cm，current density 300~330 A/m2，boiling temperature and synthesis time 76~80 h. The current efficiency is over 95 % and direct niobium transform rate is over 96 % at the optimized conditions.