Expansive soils are very important natural geological materials used in the geotechnical applications in the worldwide. After compacting, they are used as hydraulic barriers in earth structures, such as core of earth fill dams, landfill liners, and etc. However, these soils have some defects from technical points of view. To remove the defects, one of the soil improvement methods is mixing of these soils with granular materials. In this study, pine tree sawdust was used as granular additive material to stabilize the expansive soils. The effects of pine saw dust on the volume compressibility of expansive soils were investigated by using experimental studies under laboratory conditions. The test results showed that the pine saw dust positively affected the geotechnical properties in term of volume compressibility manner. As a consequently, the geotechnical properties of the expansive soil when blended with pine tree sawdust indicates that the pine tree sawdust is a good modification material for this problematic soil.