The study investigates the influence of varying proportion of Ordinary Portland Cement (OPC) in high plastic clay soil while soil-cement stabilization of road embankment. Since, high plastic clay is unsuitable as subbase material of road embankment, our study provided as a guideline for the mixing ratios of OPC in soil-cement stabilization in this regard. Unconfined compressive strength (UCS) of soil samples were increased significantly with the addition of OPC to the soil. Optimum moisture content increased with higher percentage of cement added to soil. Besides, UCS of soil-cement mixture were improved with the increase of curing period. On contrary, increasing %OPC in soil-cement stabilization is costly. The test results recommended that the addition of 10% cement was sufficient enough to gain adequate UCS within 1- day curing.