Extensive soils can be found all over the world. The clay mineral montmorillonite is predominantly responsible for soil expansion. Because of their ability to shrink and swell with seasonal changes in moisture content, these expansive soils can cause significant damage to engineering construction. To stabilize the effects of swelling soil various ground improvement techniques, incorporate mineralogical modification of clays. The application of nanotechnology increased in past few years to deal with clay minerals as it possesses the same dimensional properties. To understand the behaviour of Nano modified clay, bentonite was selected as it represents the montmorillonite clay mineral. The characterization of surface-treated bentonite by nanomaterial was carried out. The study of physio-chemical properties and textural properties of surface-modified bentonite clay was carried out. Swelling pressure was evaluated by consolidometer test. With the advanced nanotechnology instrumentation technique, particle size analysis, zeta potential, wettability, contact angle, infra-red spectroscopy, rheological properties, BET surface area, pH values, XRD, TGA, etc was carried out for treated and untreated soil, so as to understand the comparative behaviour of surface modification. It was found that by using Nano surfactant, liquid limit and shrinkage limit reduced considerably. The increase in the quantity of surfactant increases the d-spacing. Thermal stability and particle size increase after surface treatment of bentonite clay. Soil reaches a visco-elastic state and BET surface area decreased after surface modification.