The invention discloses high-performance pozzolan cement base material admixture to overcome the defects of large air shrinkage and low resistance to sulfate erosion in the application process of the conventional natural pozzolan. The performance of cement base material admixture is improved, the performance after hydration heat release and hardening is improved, the condition that building raw materials are in short increasingly is relieved, and engineering construction can be implemented smoothly. The admixture comprises the following components in part by weight: 77 parts of pozzolan, 15 parts of I-level coal ash, 4 parts of gypsum powder, 3.5 parts of polyvinyl alcohol polymer re-dispersible emulsion powder, 0.05 part of hydroxypropyl methyl cellulose and 0.5 part of calcium lignosulphonate.