The growth of La2Zr2O7 and SrZrO3 reaction layers at the cathode-electrolyte interface during the fabrication process and in operating conditions negatively affects the SOFC (solid oxide fuel cell) performance. In the present paper the effectiveness of diffusion barriers at the SOFC cathode-electrolyte interface is investigated. Thin layers of neodymium aluminate (NdAlO3) were evaporated onto yttria-stabilized zirconia (YSZ) substrates and characterized by XRD, SEM-EDS, Auger and impedance spectroscopies. The behaviour of the interfaces among YSZ, NdAlO3, barriers and the porous La0.85Sr0.15MnO3 cathode was studied as a function of the temperature between 1200 degrees C and 1500 degrees C. In this study, the conductivity of the barrier layer was found of the same order of magnitude as that of La2Zr2O7 reaction layers, but the ohmic loss of the barrier, which is expected to be constant versus time, can be minimized by a proper choice of its thickness. The barrier appears to be effective only up to T = 1200 degrees C, thus preventing the growth of zirconate layers at the cathode-electrolyte interface. Alternative barrier materials should be chosen if higher temperatures are necessary in SOFC fabrication processes.