The study investigated the changes in soil properties as a function bagasse ash proportion during soil stabilization. Addition of bagasse ash in soil during stabilization is carried out to improve the properties of soil susceptible to deformation under load effect. The bagasse ash was obtained from Costus cupreifolius mass. The experimental values obtained from maximum dry density (MDD), optimum moisture content (OMC), consistency limits, California bearing ratio (CBR) and unconfined compressive strength (UCS) were fitted to a linear model to ascertain the degree of correlation between the properties and the percentage of bagasse ash. Experimental results showed that bagasse ash improved the properties of the soil positively. Thus, the maximum dry density, optimum moisture content, and the consistency limits of the stabilized soil reduced with addition of bagasse ash, while the California bearing ratio and unconfined compressive strength of the soil were increased. The model also interpreted the fitted experimental observations with correlation coefficients ranging from 0.7501 to 0.9792. Therefore, using a mathematical model will be useful to predict the properties of soil for a given mix design without direct measurement, especially in the case where the instrument is prone to error. Application of model would also be useful for design and analysis.