Concrete is the construction material being used extensively in the world next to water. the impact of environment factors on concrete reduces the desired strength ,life, durability etc. as an alternative high strength concrete has being researched upon to improve the desired mechanical properties for meeting the structural performance of the concrete High strength concrete (HSC) is a product of high quality ingredients with high percentage cement ,aggregates, low water cement ratio, silica fume, super plasticizer etc. In this thesis the experimental set up is made to study the mechanical properties of HSC with and without plastic fibers. similarly the effect of silica fume on HSC by varying its percentage by 0% 5% 10% in the mix studied. for all mixes 25% extra fly ash has been added for cement and sand. In this experiment, comparison for compressive strength is shown between cubes made of gravel stone of (10mm) with and without fiber. The aim of this project is to observe the compressive strength with and without using plastic fibers.