This　study　sought　to　analyze　the　effect　of　curing　temperature　on　mechanical　strength　and　microstructure　of　a　copper　tailing-based　geopolymer　via　scanning　electron　microscopy　(SEM),　HCl　extraction,　nuclear　magnetic　resonance　(NMR),　and　X-ray　diffraction　(XRD).　The　distribution　of　gel　formed　in　geopolymers　tended　to　be　uniform　with　increasing　curing　temperature　from　25　to　80　degrees　C.　Moreover,　the　percentage　of　Si　sites　in　C-S-H　and　N-A-S-H　gels　increased　from　62.08%　to　78.94%　and　more　tetrahedral　[AlO4]　was　incorporated　into　the　tetrahedron　[SiO4]　backbone,　leading　to　an　increase　of　compressive　strength　from　10.2　to　39.6　MPa.　When　the　curing　temperature　was　increased　to　120　degrees　C,　the　percentage　of　Si　sites　in　C-S-H　and　N-A-S-H　gel　decreased　to　69.52%,　and　the　compressive　strength　decreased　to　27.5　MPa.　Moderately　elevated　curing　temperature　promoted　the　dissolution　of　aluminosilicate　while　curing　temperatures　above　80　degrees　C　hindered　it.　Excessive　curing　temperature　led　to　a　decrease　in　the　geopolymer　alkaline　medium.　(C)　2020　Elsevier　Ltd.　All　rights　reserved.