Expansive Soil Geotechnical Properties Stabilized with Plastic Powder and Lime Expansive soil is considered defective due to the large volume change it undergoes for any moisture fluctuation. There are several engineering solutions to the problems these soils pose to the structures built on them. At times when removing the defective soil is uneconomical or impractical, stabilizing the soil with waste plastic powder has both economic and environmental benefits. This research work is aimed at evaluation of the suitability of waste plastic powder for use in stabilization of expansive clay soil.plastic bottles collected and crushed in to powder form in factory.the grain size distribution of plastic powder based on AASHTO spesfication manual 6.4% in the range of gravel 43.5% in the range of sand 50.1% in the range silt.The laboratory work involved index properties to classify the soil. an investigation of the soil shows that it belongs to the A-7-5 class of soil in the AASHTO soil classification system. Soils under this class are generally of poor engineering use. Atterberg limits, specific gravity, free swell, compaction and CBR tests were used to evaluate properties of stabilized soil. The soil was stabilized with waste plastic powder in a stepped concentration of 2%, 4%,6%, 8%, 10% and 12% by dry weight of the soil. Analysis of the results shows that slight improvement on the geotechnical properties of waste plastic powder stabilized soil. Waste plastic powder reduces plasticity index 75% to 51% at 8%, free swelling 130%to 69.5% at 10%, MDD 1.3 to1.13, CBR Swell 7.4% to 3.3% with an increase in OMC 30%to 49.5% at 12% and CBR 0.9% to 2.3%at10%. From this study, it was found out that waste plastic powder stabilized soil does not meet the minimum requirement of ERA pavement manual specification for use as a sub-grade material in road construction. To make plastic powder applicable for stabilization and examine the effect of lime on plastic powder additional tests also incorporated by adding 4% of lime with 6%,8%,10%&12% waste plastic powder. The results indicate that lime in combination with waste plastic powder is suitable for improving the plasticity index, swelling and CBR. Therefore, this study shows that lime in combination with plus waste plastic powder can be effectively used to improve expansive soils with soaked CBR value and high plasticity.