Abstract: In order to study the weak alkaline activation technology of geopolymer, alkali activation of geopolymer was studied using the shale vanadium tailings in Hubei Province as raw materials. The effects of different addition of metakaolin, modulus of activator and dosage of activator on the compressive strength of geopolymer were studied. Finally, the compressive strength of the geopolymer sample can reach 27.55 MPa in 3 days under the activation system of m(shale vanadium tailings):m(metakaolin) is 9:1, the modulus of weak alkaline activator Na₂SiO₃ is 3.0 and the dosage of activator is 14%, which greatly improves the compressive performance of the geopolymer. The phase transition, chemical bond change and micro-morphology of the geopolymers prepared under different modulus sodium silicate were analyzed. It was found that the quartz in the vanadium tailings is further dissolved under the action of liquid sodium silicate. The dissolved amorphous silicon and aluminum compounds react with silicates in liquid sodium silicate to form silica-alumina gel phases. Silicates in the liquid sodium silicate acts as an inducer, the higher the modulus of the liquid sodium silicate is, the higher the content of silicates is, and the faster the reaction between the liquid sodium silicate and amorphous silicon and aluminum compounds in vanadium tailings is. Thus, more silica-alumina gel phases are formed and the compressive strength of geopolymer is improved, and the safe preparation of geopolymer has been realized.