Expansive soils are highly problematic in civil engineering due to their tendency to undergo significant volume changes with variations in moisture content. These soils swell when exposed to water and shrink upon drying, leading to structural damage such as cracks in pavements, foundations, and buildings. Stabilization of such soils is essential to enhance their engineering properties and ensure the durability of structures. This study focuses on the stabilization of expansive soil using TerraZyme, a bio-enzyme stabilizer, and sugarcane ash, an agricultural waste material. TerraZyme acts by improving the bonding between soil particles, reducing voids, and minimizing water absorption, thereby enhancing soil strength and durability. Sugarcane ash, rich in silica, exhibits pozzolanic properties that contribute to increased soil stability through chemical reactions with soil minerals. The combined use of these materials provides a sustainable and eco-friendly solution for soil stabilization. In this project, soil samples are collected and subjected to various laboratory tests such as Atterberg limits, Proctor compaction, California Bearing Ratio (CBR), and Unconfined Compressive Strength (UCS). Different proportions of sugarcane ash are mixed with soil, and TerraZyme is added in diluted form. The samples are cured for specific periods, and their performance is evaluated based on improvements in strength and reduction in swelling characteristics. The results indicate a significant improvement in the engineering properties of expansive soil, including increased load- bearing capacity, reduced plasticity, and enhanced compaction characteristics. The study concludes that the combination of it is concluded that the use of TerraZyme and sugarcane ash together is an efficient, economical, and eco-friendly technique for stabilizing expansive soils, particularly for applications in road and foundation construction. The study concludes that the combination of TerraZyme and sugarcane ash is an effective, economical, and environmentally friendly method for stabilizing expansive soils, making it suitable for applications in road construction and foundation engineering