Glass fibre reinforced concrete is recent development in the field of concrete technology. Concrete being the most important and widely used material is called upon to possess very high strength and sufficient workability properties. The concrete has more desirable properties like High compressive strength, stiffness, durability. At the same time concrete is brittle and weak in tension. To improve the concrete properties, the system was named glass- fibre reinforced concrete view the alkali resistance glass fibre is used. In thefirst part of experimental investigation, the glass fibre has been used to study the effect on compressive strength on M15, M20 amp M25 grade of concrete for different % of glass fibreie., 0%,3%, 5%, 7% by weight of aggregates. And in todayrsquos world the main emphasis is on green and sustainable development. Presently large amount of fly ash is generated in thermal power plants as a waste material with an improper impact on environment and humans. Fly ash is difficult to decompose, so using fly ash is a major step towards sustainable development. Also, Cement industry is one of the major contributors to pollution by releasing carbon dioxide. So, by partially replacing cement with pozzolanic material such as fly ash, the cement industry can serve both the purposes of meeting the demands of construction industry and at the same time providing a green and clean environment. This research workincludes second part whichinvestigates the behavior of concrete and optimum percentage while replacing fly ash in different proportions.nbsp The cement has been replaced accordingly in the range of 0%, 18%, 20% amp22% by weight of cement of M25 grade concrete. Concrete mixtures were produced, tested and compared in terms of compressive strength, as an alternative to traditional concrete.