The　development　of　nanostructured　electrodes　of　solid　oxide　cells　is　largely　hindered　by　the　high　temperature　sintering　process　and　limited　in　the　loading　and　choices　of　catalytic　phases.　Here,　a　nanostructured　multi-phase　air　electrode　is　fabricated　via　facile　combination　of　Gd0.2Ce0.8O1.9　(GDC)　decorated　PrBa0.8Ca0.2Co2O5+delta　(PBCC)　and　direct　assembly　approach.　The　highly　flexible　decoration　process　and　the　in　situ　formation　of　multi-phases　lead　to　the　formation　of　intertwined　core-shell　type　nanostructures　with　intimate　electrode/electrolyte　interface.　A　cell　with　a　40　wt%　GDC　decorated　PBCC　electrode　achieves　a　peak　power　density　of　1.74　W　cm(-2)　at　750　?　and　an　electrolysis　current　density　of　1.77　A　cm(-2)　at　1.3　V　with　excellent　durability　for　200　h.　The　combined　decoration　and　direct　assembly　approach　provides　a　unique　and　general　pathway　to　develop　a　new　class　of　nanostructured　air　electrodes　for　efficient　and　durable　solid　oxide　cells.