The use of supplementary cementitious materials is well accepted because of the several improvements possible in the concrete mix, for the overall economy. The present work is a support to use the waste product from steel industry is helpful in cement which also helps to reduce the carbon footprint. In recent years Blast Furnace Slag when replaced with cement has emerged as a major alternative to conventional concrete and has rapidly gained the concrete industry's attention due to its cement savings, energy savings, cost savings, socio-economic and environmental benefits. The present study reviews the results of an experimental study, conducted by various authors to evaluate the strengths and strength efficiency factors of hardened concrete, by partially replacing the cement by various percentages of ground granulated blast furnace slag and fly ash. The optimum GGBS and fly ash replacement as the cementitious material is characterized by high compressive strength, low heat of hydration, resistance to chemical attack, better workability, good durability and cost-effective.