With　the　yearly　increase　of　crude　steel　production,　the　accumulated　storage　volume　of　steel　slag　in　China　is　also　rising,　and　the　use　of　steel　slag　as　supplementary　cementitious　material　is　an　effective　measure　to　improve　the　comprehensive　utilization　rate　of　steel　slag　and　reduce　the　carbon　emission　of　cement　and　concrete　industry.　However,　steel　slag　has　problems　such　as　low　content　and　low　activity　of　the　cementitious　component　and　high　content　of　swelling　components,　which　limit　its　application　in　cement　and　concrete.　At　present,many　methods　are　used　to　improve　the　cementitious　activity　and　volume　stability　of　steel　slag,　including　mechanical　grinding　activation,　high　temperature　activation,　acid　activation,　alkali　activation,　organic　activation　and　carbonization　activation.　Mechanical　grinding　activation　mainly　through　the　physical　way　to　break　the　steel　slag　crystal　structure　and　reduce　the　particle　size,　but　it　has　high　energy　consumption　and　only　for　the　early　strength　benefit.　High　temperature　activation　mainly　includes　high　temperature　curing　and　high　temperature　reconstruction.　High　temperature　curing　promotes　hydration　by　changing　the　external　environment　in　which　the　steel　slag　is　hydrated,　but　the　higher　temperature　will　cause　the　decomposition　of　ettringite　and　introduce　pores.　High　temperature　reconstruction　process　directly　changes　the　mineral　composition　of　the　steel　slag,　but　there　are　problems　such　as　high　energy　consumption　and　poor　homogeneity.　Alkali　activation　can　promote　ion　dissolution　and　consume　calcium　hydroxide,　but　there　are　problems　such　as　alkali　aggregate　reaction　and　efforescence.　Acid　activation　can　promote　ion　dissolution　and　increase　the　specific　surface　area　of　steel　slag,　but　it　will　react　with　the　active　components　in　steel　slag.　In　organic　activation,　alkanolamines　can　promote　ion　dissolution　through　complexation,　but　the　mechanism　of　action　of　alkanolamines　with　different　molecular　structures　is　still　unclear.　Carbonation　fills　the　pores　through　the　reaction　of　calcium　and　magnesium　minerals　with　CO2　to　form　carbonates　as　microaggregates,　but　the　presence　of　CO2　diffusion　resistance　to　the　interior　of　the　specimen　will　make　the　carbonation　degree　uneven　inside　and　outside.　This　paper　analyzes　the　reasons　of　low　activity　and　poor　volume　stability　of　steel　slag　from　the　source　and　composition　of　steel　slag,　summarizes　the　common　methods　for　improving　the　cementitious　activity　and　volume　stability　of　steel　slag,　points　out　the　current　dilemmas　faced　by　various　methods　and　makes　certain　outlooks,　in　order　to　provide　references　for　further　optimization　of　steel　slag　properties　and　promote　the　further　application　of　steel　slag　in　the　cement　and　concrete　industry.　©　2023　Cailiao　Daobaoshe/　Materials　Review.　All　rights　reserved.