This work aims to investigate the factors to affect the compressive strength and design the optimum formulation of slag-metakaolin-based geopolymer. The 60% slag and 40% metakaolin were used as the raw materials. The effects of alkaline activator concentration modulus and liquid tosolid ratio on the 7 and 28 d compressive strength of the slag-metakaolin-based geopolymer were nasalized. The results show that the compressive strength of the slag-metakaolin-based geopolymer increases with the increase of the concentration of the activator. That will decrease with the increase of the liquid-solid ratio. In a certain range，the compressive strength of the slag-metakaolin-based geopolymer increases and then decreases with the increase of the activator modulus. Moreover，the liquidto solid ratio plays a key role to affect the strength. When the liquid to solid ratio is 0.9 the maximum compressive strength of 76.03 MPa will be obtained. The slag-metakaolin-based geopolymer exhibited high early strength， whereas the strength of the 28 d aging increases rarely