Cathodic polarization of LaxSryMnO3 (x = 0.3-0.6; y = 0.3-0.5) electrodes, doped by the sintering agents Bi2O3, PbO, Sb2O3, CuO, or Bi2CuO4, on a zirconia solid electrolyte has been studied. The electrochemical activity of La0.6Sr0.4MnO3 electrodes with sintering agent Bi2CuO4 was found to be the highest among the solid solutions based on La(Sr)MnO3. The positive effect of the bismuth cuprate addition is ascribed to the sufficiently high mixed ionic and electronic conductivity of Bi2CuO4. The obtained results are characterized by the absence of a direct correlation between the electrochemical parameters of the electrode layers and oxygen permeability of the manganite ceramics. It was found that oxygen transport through the manganite ceramics is limited by the sorption of on ceramics surface.