This study explored the utilization of nano-silica (NS) and Sugarcane Bagasse Ash (SCBA) as a replacement of cement and assessed for mechanical properties. Concrete mixes were prepared by replacing cement with 15% SCBA and incorporating incremental doses of NS ranging from 1 to 5% by weight of binder. Compressive strength split tensile strength and flexural strength tests were conducted at different curing periods (7, 28 and 56 days) for concrete mixes with 15% SCBA and incremental additions of Nano-silica ranging from 1 to 5%. The performance of these mixes was compared with the nominal mix to quantify the improvement in mechanical properties. The maximum strength is achieved for replacement of 15% SCBA and 2% NS addition in cement. This specific mixture showed a large improvement in mechanical indices: a 24.23% increase in compressive strength is noticed, as well as a noticeable increase in split tensile strength by 28.12% after 28 days, 10.33% increase in flexural strength at day 56. The incorporation of SCBA and NS was considered as a viable option for the replacement of cement to safeguard the environment. This combination of mix not only enhances the mechanical properties of mixes at later ages. The study supports the development of sustainable concrete by utilizing agro-industrial waste and nanomaterial’s to reduce cement consumption without compromising structural integrity.