The Aim of this paper is to Stabilize Expansive soil of Sub Grade and to improve its California bearing ratio and free swell index and other properties using Industrial Waste materials Iron Sludge. Expansive soil have tremendous strength but it becomes very soft when it getting wet, It expands/swells due to its mineralogical composition during its wet condition, It creates cracks or consolidated when it is dry. Expansive soils can be found on almost all the continents on the Earth. Destructive results caused by this type of soils have been reported in many countries. First of all, identify the engineering properties of soil and then add 5, 10… 30 % iron Sludge in natural Soil. And again check the change in engineering properties of soil like plastic limit, plasticity Index, swelling Index of treated soil. By comparing the test results of virgin soil and treated soil we check the feasibility of using Iron Sludge for stabilization of expansive soil.