Concrete is one of the materials in the construction industry for which the usage has diversified all over the globe. Cement manufacturing releases harmful gases like CO2 during its production. So, to create a sustainable environment and save natural resources, alternate construction materials can be effectively used without sacrificing the required quality. The present work is taken up to determine the effect of polyester fibres on the strength characteristics of concrete with micronized silica (MS). MS is obtained by controlled burning of rice husk which is a by-product in rice mill industries. Cement was partially replaced by MS in different proportions of 0%, 5%, 10%, 15% and 20% by weight of cement in the conventional concrete. To rectify the problem arrived by using MS, i.e., high level of water absorption, a good water reducer (superplasticizer) was used. Polyester fibres were added to the micronized silica concrete mix which gave the optimum strength in the proportion of 0%, 0.1% and 0.2% by weight of cement. Compressive, split-tensile and flexural strength were determined, and the results indicated that the strengths of concrete along with MS were increased upto a limit, and thereafter it reduces and fibres further enhance the strength. The ideal mix was obtained at MS content of 10%and fibre addition of 0.2% for the concrete.