A novel method for preparation of alkali-activated metakaolin/granulated blast furnace slag (GBFS)-based geopolymer reinforced by organic resins (OR) was reported. The geopolymer composites by doping an amount of 1 wt% OR displayed the highest compressive and flexural strengths at the different curing times. The calorimetry results showed that the reaction heats of the geopolymer composites at the early reaction stage of 1 similar to 3d are much higher than that of geopolymer due to the geopolymerization rate to be accelerated by incorporation of OR. A reasonable reinforced mechanism was proposed.