Residual soils are referred to soils that formed through process of physical and chemical weathering of in-situ rocks. Reactions of various physical and chemical weathering agents had resulted in physical and chemical variability of residual soil and site dependent. The structure and minerals of in-situ rock were degraded physically and chemically and thus making its less resistance to load compared to un-weathered parent rock. Hence, it is important to stabilize the residual soil. Different ratios of blended hydrated lime and Ground Granulated Blast Furnace Slag (GGBS) namely 10:0, 9:1, 8:2 and 5:5 were utilized in this study. The percentage of admixtures was set at 10% with respect to its dry mass of soil. Unconfined compressive strength of treated soil specimens were determined after 7 days, 14 days and 28 days of humid curing. The water contents of the specimens were found to decrease slightly with an increment of curing periods while the strengths of the stabilized specimens were increased with curing periods. The highest unconfined shear strength at 28 days was recorded as 321.74 kPa with 8.18% axial strain. Thus, it showed that the use of blended lime and slag can improve the strength of residual soil. However, the treated samples failed to achieve the minimum strength increment of 345 kPa to be considered as an effective stabilization as stated in ASTM D4609. Some other factors namely curing temperature and Initial Consumption of Lime (ICL) should be considered to optimize the strength of the stabilized materials.