Some peculiarities of the mechanism and kinetics of non steady anode process at the platinum in the KF-NaF-AlF 3-Al 2O 3 melt in dependence on temperature (750, 780°C), potential sweep rate (0.01-10 V/s), and atmosphere (argon, oxygen) in closed experimental cell were investigated using chronovoltammetry technique. A wave corresponding to evolution of molecular oxygen and a peak preceding it, possibly, of the electrochemical oxidation of platinum with formation of Pt^O were specified in the volt-amper dependences. The system of algebraic equations, describing the volt-amper dependence of quazistationary (0.01 V/s) discharge of oxide-fluoride anions at the platinum anode, considering electrochemical formation and chemical decomposition of platinum oxide compound Ptj-O. The comparative analysis of experimental and calculated volt-amper dependences was carried out.