Geopolymer concrete can be expressed as "concrete without cement". Geopolymer concrete is environmentally friendly and an inventive way to replace the conservative concrete which contributes 7-8% of total CO2 production in the world. “The concrete which entails of the source materials and the alkaline solution”. The source material can be from agricultural wastes such as Bagasse ash, Rice husk ash, Palm fuel ash, etc and the industrial by-products such as Fly ash, Ground Granulated Blast Furnace Slag, Copper Slag, etc. The alkaline solutions can be either sodium hydroxide and sodium silicate or potassium hydroxide and potassium silicate. In the present study, an effort has been made to check the likelihood of reuse of bagasse ash in Geopolymer Concrete by probing mechanical properties of M30 grade concrete for 0, 25, 50, 75 and 100 percent replacement by bagasse ash. The behavior of 100% GGBS replaced concrete under elevated temperature by weight loss, residual strength, cracking pattern and spalling pattern.