Abstract: This study aimed to evaluate the strength properties of geopolymer concrete using fly ash and ground granulated blast furnace slag (GGBS) with the addition of a super plasticizer at a grade M20. The study used 70% fly ash and 30% GGBS to replace the cement content of the concrete mix, and sodium hydroxide and sodium silicate were used as Alkaline activators. The concentration of (NaOH) solution was maintained at 8 molarity and the dosage of activator ratio is 2.5 is a combination of sodium silicate and sodium hydroxide ratio. The compressive strength of the geopolymer concrete was tested at different ages (7, 14, and 28 days) to evaluate the strength properties. The results showed that the addition of fly ash and GGBS significantly improved the strength properties of the geopolymer concrete. Moreover, the optimized dosage of the super plasticizer was found to be 1% of the total weight of the mix. The study concludes that the use of fly ash and GGBS in geopolymer concrete can significantly improve its strength properties, and the addition of a super plasticizer can enhance its workability. This finding suggests that geopolymer concrete could be a viable alternative to conventional concrete in construction applications .The test result shows encouraging results of ordinary Portland cement concrete and geo polymer concrete so one can easily replace ordinary concrete with geopolymer concrete for precast applications.