Neutralization slag (NS) is an industrial waste residue with calcium sulfate as the main component produced by mineral mining and metallurgical treatment processes. The large accumulation and storage of NS will pose a great threat to the environment. Thereforeit is urgent to explore a new technology for recycling NS. The mechanical properties of NS based geopolymers with different granulated blast furnace slag (GBFS) blending levels were investigatedand the phase compositionhydration ratepore structure and micromorphology of the NS geopolymer were characterized by X-ray diffractionreaction heat testingmercury intrusion porosimetryFourier-transform infrared spectroscopy testing and scanning electron microscopy. The results show that the main product of the geopolymerisation between NS and GBFS under the action of activator is C(N)-A-S-H gel. The incorporation of GBFS can increase the rate of polymerization reaction generate more geopolymer gelsmake the microstructure of NS based geopolymer denser and the mechanical properties higher. The 28 d compressive strength of the NS based geopolymer with 30%(mass fraction) granulated blast furnace slag can reach 17.8 MPa.