The present invention relates to a geopolymer concrete formed by curing a mixed composition comprising a binder composition which includes, by weight of total binder composition, 50% to 60% of granulated blast furnace slag, 10% to 15% of fly ash and 25% to 30% of palm oil fuel ash; an alkaline activator solution that has a binder to alkaline activator solution weight ratio of 1 : 0.4 to 0.5; a sand that has a binder to sand weight ratio of 1 : 2 to 2.5; and water, which has a water to binder weight ratio of 0.2 to 0.35 : 1.