Expansive soils present substantial geotechnical engineering concerns due to their potential for excessive swell-shrink behaviour, leading to structural damage and stability issues. This research study which aimed at using xanthan gum (XG), a natural biopolymer, as an eco-friendly adhesive material to enhance the strength properties of expansive soil. Biopolymer XG was inserted into the expansion soil sample from 0.5 to 2% dry mass of soil concentrations. Laboratory study was conducted on treated soil samples to assess their strength characteristics measured in terms of unconfined compressive strength (UCS), California Bearing Ratio (CBR) and direct shear. Test results exhibited an increase in the UCS and CBR values of the expansive soil for every mix ratio with XG as compared to the untreated soil, which implied improvements on bearing capacity and shear strength. Based on the direct shear tests, it showed that the cohesion and newly angle of internal friction of treated soil increased with time after treatment, hence increase in overall strength in shears. The adhesive action is the result of XG synthesis where it establishes a cross-linked framework within the soil medium, and it enables to gel the soil particles keeping them together along with a capacity for reducibility of its volume as well. It was shown that an optimal dosage of 1.5% XG provided the highest strength enhancement compared with untreated soil. This discovery implies that the XG biopolymer has a high potential of becoming suitable adhesive material in eco-friendly due to its geotechnical properties in relieving expansive soil.