<p>This study investigates the effectiveness of fly ash-based geopolymer concrete was conducted to be used as an alternative material to replace the normal concrete. The concrete mixture was prepared by mixing fly ash, fine aggregate, nano-slag, and SP in Na2SiO3/NaOH solution. The mixture was divided into three different groups, with constant water to fly ash ratio of 0.1, and different alkaline content: 0.4, 0.45, and 0.5 of fly ash rather than two curing techniques (moist and autoclave). Several hardeness properties of concrete like compressive strength, density; and splitting tensile strength were examined after 28 d. The microstructural development of geopolymer concrete was monitored using X-Ray Diffractometer. Based on the results of this investigation, it is recommended to cure the geopolymer concrete by autoclaving rather than the traditional moist technique, especially at lower alkaline dosage. However, the partial addition of nano slag by weight of FA had a positive effect on both curing techniques.</p>