In　this　study,　blast　furnace　slag　(BFS)　was　used　instead　of　partial　complex　Portland　cement　(PC)　to　produce　slag　foam　concrete　(SFC),　aiming　to　improve　the　ion　attack　resistance　and　compressive　strength　of　nature　foam　concrete　(NFC).　The　behavior　of　compressive　strength,　pore　structure,　hydration　products,　and　microstructure　of　SFC　in　salt　environments　(5%　Na2SO4,　5%　NaCl,　5%　Na2SO4+5%　NaCl)　was　investigated.　The　findings　indicate　that　the　negative　effect　on　the　compressive　strength　of　sulfate　is　mitigated　by　chlorine.　In　NFC,　the　loss　of　compressive　strength　in　the　Na2SO4,　Na2SO4+NaCl,　and　NaCl　solution　at　120　days　is　18.06%,　12.28%,　and　3.58%,　respectively.　The　optimization　of　SFC　by　the　addition　of　BFS　first　increases　with　the　amount　of　replaced　cement　until　the　positive　effect　of　BFS　is　overshadowed　by　its　negative　effect　when　the　amount　replaced　reaches　50%.　And　the　salt　erosion　resistance　of　SFC　with　30%　of　cement　replacement　is　the　best　of　all　mixtures　with　KSO　and　KSO　of　0.89　and　0.94　respectively.　In　the　beginning,　the　SO42-　and　Cl-　promote　the　production　of　more　ettringite　(AFt)　in　the　SFC,　which　results　in　the　filling　of　the　original　cracks　and　a　reduction　in　pore　volume.　The　opposite　situation　gradually　occurs　in　SFC　owing　to　the　expansion　of　the　AFt,　as　salt　curing　continues.　The　content　of　hydration　products　varies　according　to　the　amount　of　BFS　added,　and　a　decrease　in　Ca(OH)2　and　an　increase　in　the　gel　are　observed　in　SFC　with　30%　−50%　of　cement　replacement　compared　to　NFC.　©　2023　Elsevier　Ltd