To　address　the　issues　of　poor　acid　resistance　of　cement-stabilized　soft　soil　and　the　high　pollution,　energy　consumption,　and　cost　associated　with　cement　production,　this　study　proposes　using　low-cost　industrial　solid　wastes　(ground　granulated　blast　furnace　slag　(GGBFS)　and　fly　ash　(FA)　in　varying　ratios)　as　precursors,　with　solid　sodium　hydroxide　as　the　activator,　to　prepare　geopolymer　grout　through　a　＇one-step＇　process　for　stabilizing　soft　soil.　Subsequently,　the　geopolymer-stabilized　soft　soil　samples　were　immersed　in　HNO3　and　H2SO4　solutions　with　different　pH　values　(2,　4,　and　6).　The　acid　resistance　of　the　stabilized　soil　was　evaluated　at　different　erosion　ages　(30,　60,　120,　and　240　days)　using　four　indices:　mass　loss,　unconflned　compressive　strength　(UCS),　neutralization　depth　(ND),　and　pH　value.　Furthermore,　the　changes　in　microstructure　and　hydration　product　composition　of　the　samples　under　different　acidic　environments　were　investigated　using　scanning　electron　microscope-energy　dispersive　spectrometer　(SEM-EDS)　to　reveal　the　degradation　mechanisms.　The　test　results　indicate　that　compared　to　H2SO4　solution,　HNO3　solution　exerts　a　milder　acid　erosion　effect　on　the　stabilized　soft　soil.　This　is　primarily　because　the　Ca2+,　K+,　and　Na+　ions　in　the　stabilized　soil　form　nitrates　in　water,　which　can　neutralize　the　erosion　of　NO-3　ions,　thereby　mitigating　the　degradation　of　the　soil＇s　properties.　When　the　mass　ratio　of　GGBFS　to　FA　is　80:20,　the　acid　erosion　resistance　of　the　geopolymer-stabilized　soft　soil　reaches　an　optimal　level.　This　suggests　that　the　appropriate　incorporation　of　FA　can　fonn　a　dense　microstructure　in　the　samples,　effectively　impeding　the　intrusion　of　H+,　NO-3　and　SO2-4　ions.　The　research　findings　can　expand　the　application　scope　of　low-cost　industrial　solid　wastes　and　lay　a　theoretical　foundation　for　the　durability　assessment　of　one-step　geopolymer-stabilized　soft　soil.　©　2025　Biodiversity　Research　Center　Academia　Sinica.　All　rights　reserved.