Reversing　the　direction　of　polarization　current　is　essential　for　reversible　solid　oxide　cells　technologies,　but　its　effect　on　cobaltite　based　perovskite　oxygen　electrodes　is　largely　unknown.　Herein,　we　report　the　operating　stability　and　microstructure　at　the　electrode/electrolyte　interface　of　La0.57Sr0.38Co0.18Fe0.72Nb0.1O3-delta　(LSCFN)　oxygen　electrodes　assembled　on　barrier-layer-free　Y2O3-ZrO2　electrolyte　under　cyclic　anodic/cathodic　polarization　mode　at　0.5　A　cm(-2)　and　750　degrees　C.　During　the　cyclic　polarization,　the　electrocatalytic　activity　of　LSCFN　electrode　is　drastically　deteriorated　in　cathodic　mode,　but　the　performance　loss　is　largely　recoverable　in　anodic　mode.　This　is　due　to　the　fact　that　the　surface　segregation　of　Sr　and　accumulation　at　the　electrode/electrolyte　interface　by　cathodic　polarization　can　be　remarkably　mitigated　by　anodic　polarization.　The　time　period　in　each　cycle　plays　a　key　role　in　determining　the　accumulation　of　Sr　species　at　the　electrode/electrolyte　interface.　A　full　cell　operating　in　a　time　period　of　12　h　fuel-cell/12　h　electrolysis　is　reversible　for　a　duration　of　240　h,　in　contrast　to　the　performance　degradation　in　a　shorter　time　period　of　4　h　fuel　cell/4　h　electrolysis.　The　present　study　sheds　lights　on　applying　cobaltite　based　perovskite　oxygen　electrodes　on　barrier-layer-free　YSZ　electrolyte　for　reliable　solid　oxide　cells.