Microstructure　of　cast　SAF2906　duplex　stainless　steel　was　studied　qualitatively　at　850　℃　for　different　time.　The　double-loop　electrochemical　potentiokinetic　reactivation　(DL-EPR)　was　optimized　through　studying　the　influences　caused　by　three　factors　(scan　rate,　temperature　and　the　concentration　of　the　electrolyte).　The　DL-EPR　test　results　show　that　the　optimal　conditions　is:　solution　media　1.0　mol/L　HCl+2.0　mol/L　H　2　SO　4　,　the　solution　temperature　of　30　℃,　scanning　rate　1　mV/s.　Then　the　resistance　to　intergranular　corrosion　of　cast　SAF2906　DSS　was　tested　by　optimized　DL-EPR.　The　results　show　that　the　volume　fraction　of　σ　phase　increase　with　the　sensitization　time　increasing.　Through　comparing　morphologies　of　the　samples　for　different　sensitizing　temperature,　the　reliability　of　DL-EPR　for　evaluating　intergranular　corrosion　resistance　of　the　cast　SAF2906　steel　is　verified.　©　2018,　Editorial　Office　of　＂Jinshu　Rechuli＂.　All　right　reserved.