Degradation of solid oxide electrolysis cell is probably the main problem in the field of high temperature steam electrolysis. In this study two anode-supported solid oxide fuel cells were tested as a solid oxide electrolysis cell operating from 875 °C to 950 °C at the applied voltage of 1.5 V and 1.7 V respectively. Microstructural and chemical changes of the cell components were studied by field emission scanning electron microscope (FESEM), and X-ray diffraction (XRD) analysis before and after the electrolysis. FESEM analysis shows a delamination of anode layer from the electrolyte. Furthermore, formation of impurities like yttrium silicate at the cathode-electrolyte interface and lanthanum zirconate (LZ) at the anode-electrolyte interface were observed after electrolysis. It also reveals that lanthanum zicronate is formed only at the interfaces between anode functional layer La0.65Sr0.3MnO3-δ (LSM)/8 mol% yttria stabilized zirconia (YSZ) and electrolyte layer (YSZ) but not at the whole anode layer. Formation of LZ is attributed to the high partial pressure of oxygen at the anode-electrolyte interface while yttrium silicate is formed due to the diffusion of silica from glass sealant into the cathode layer. © 2014 Elsevier B.V.