The　development　of　core　component　materials　is　one　of　the　key　issues　for　the　engineering　application　of　advanced　energy　systems.　A　Fe-18Ni-12Cr-3A1　alumina-forming　austenitic　(AFA)　alloy　without　the　addition　of　C　and　Nb　was　fabricated　by　vacuum　induction　melting　and　post　hot　deformation　treatments.　In　order　to　evaluate　its　stability　during　long　term　service,　the　evolution　of　microstructure　and　mechanical　properties　during　aging　at　the　target　application　temperature　of　700　degrees　C　was　investigated.　Laves　phase　begins　to　precipitate　along　grain　boundaries　after　aging　for　10　h.　After　aging　for　100　h,　the　amount　of　Laves　phase　along　the　grain　boundaries　increase　obviously,　but　still　almost　no　precipitate　forms　inside　the　grains.　Apart　from　continuously　increased　Laves　phase　along　the　grain　boundaries,　a　lot　of　NiAl　particles　precipitate　inside　grains　after　aging　for　1000　h.　Obvious　age　hardening　occurs　after　aging　for　1000　h,　due　to　the　precipitation　of　NiAl　phase,　which　results　in　significant　increase　of　tensile　strength　at　room　temperature.