Alkali-activated　cementitious　material　(AACM)　based　on　the　utilization　of　solid　waste　is　a　new　type　of　environmentally　friendly　inorganic　material,　which　has　the　advantages　of　early　strength,　fast　hardening,　high　strength,　and　better　durability.　The　reactivity　of　solid　waste　powder　is　a　key　factor　for　its　appropriate　utilization　in　alkali-activated　cementitious　materials,　necessitating　a　rational　evaluation　of　its　reactivity.　The　reactivity　evaluation　was　conducted　on　various　solid　waste　powders,　including　fly　ash　(FA),　red　mud　(RM),　recycled　micro-powder　(RMP),　red　brick　powder　(RBP),　coal　gangue　powder　(CGP),　and　cement　kiln　dust　(CKD).　The　effects　of　NaOH　concentration,　weight　ratio　of　water　to　solid　waste　powder　(W/P)　and　curing　humidity　on　the　compressive　strength　were　investigated，then　the　compressive　strength　under　optimal　conditions　was　determined　based　on　response　surface　analysis.　The　compressive　strength　under　optimal　conditions　was　used　to　evaluate　the　reactivity　of　solid　waste　powders.　Moreover,　microscopic　tests　(e.g.,　XPS　test,　ICP　test,　and　NMR　test)　were　carried　to　evaluate　the　reactivity　of　the　solid　waste.　The　relative　number　of　bridging　oxygen　(RBO)　measured　by　the　NMR　method　in　conjunction　with　chemical　composition　analysis　serves　as　an　effective　method　for　evaluating　the　reactivity　of　solid　waste　powders.　The　leaching　rate　of　Silicon　(Si)　and　Aluminum　(Al)　ions　in　the　ICP　method　depended　mainly　on　the　NaOH　concentration　and　the　elemental　content　in　the　raw　material.　In　addition,　the　binding　energies　of　O1s,　Si　2p,　and　Al　2p　tested　by　the　XPS　method　had　no　particular　correlation　with　the　compressive　strength.　©　2023　Elsevier　Ltd