Alkali-activated　slag　(AAS)　is　used　as　a　green　cementitious　material　with　high　strength　and　good　durability,　while　the　cracking　damage　due　to　high　shrinkage　limits　the　application　of　AAS　in　engineering　project.　The　tensile　stresses　due　to　shrinkage　can　easily　lead　to　the　cracking　of　structures,　while　basic　tensile　creep　can　relax　part　of　the　tensile　stresses　and　reduce　the　cracking　risk.　This　study　aims　to　investigate　the　effect　of　nickel　slag　(NS)　on　the　basic　tensile　creep　of　alkali-activated　slag/nickel　slag　mortars　(ASNms).　NS　content　refers　to　the　weight　ratio　of　NS　to　the　summation　of　slag　and　NS.　The　properties　of　ASNms,　including　microstructure,　hydration　heat,　internal　relative　humidity,　mechanical　properties,　autogenous　shrinkage　and　basic　tensile　creep,　are　studied.　Results　show　that　the　mechanical　properties　of　ASNms　decrease　with　the　increase　in　NS　content.　By　reducing　the　hydration　degree,　the　incorporation　of　NS　decreases　the　amount　of　calcium　aluminosilicate　hydrate　(C-(A-)S[sbnd]H)　of　ASNms,　and　the　internal　relative　humidity　and　nominal　crystal-binder　ratio　of　ASNms　are　increased.　As　a　result,　the　autogenous　shrinkage　of　ASNms　was　significantly　mitigated　by　incorporating　NS.　Autogenous　shrinkage　is　the　driving　force　of　tensile　creep.　With　the　increase　in　NS　content,　the　Na+　content　absorbed　by　C-(A-)S[sbnd]H　decrease,　and　therefore　reduces　the　basic　tensile　creep　of　ASNms.　©　2022　Elsevier　Ltd