Dispersive soils have a high proportion of sodium ions that can be exchanged and are highly erodible. There are difficulties in lowering the dispersion potential of the dispersive soils. Chemical stabilization with different additions like lime, cement, bitumen, resin, etc. is a common technique for improving dispersive soils. Utilizing the mentioned materials presents advantages and specific limitations in both technical and financial aspects (Abbasi et al. in Geotech Geol Eng 36:327–335, 2018). The present study endeavors to enhance the stability of dispersive soil by incorporating rice husk ash in several ratios (5, 10, and 15%). The soil sample used in the test was Sodium Bentonite. And by conducting a Double Hydrometer test, it was found to be dispersive. The possibility for dispersivity and other characteristics of dispersive soil are examined in the current study. The addition of RHA significantly changed the dispersive nature of the soil (Ali et al. in Geotech Geol Eng 10:117–134, 1992). The findings show that the application of 10% RHA has the lowest potential for dispersivity and further adding 15% RHA the dispersivity gets increased.