Abstarct: There are soils in nature that are sensitive by increasing moisture. This soils may be increase or decrease in volume change and structure with or without load application in wetting that defined as problematic soils. Expansive and collapsible soils are two types of problematic soils that the collapse of soils is distructive and cause damage in all structures and Loess soil is the most common of collapsible soils. Various researchers consider this topic and offer the solutions. One of the solutions for prevention of collapse is stabilization and improvement soils. In this experimental study, consider the kalale loess soil and calculated the collapse potential for it, and then stabilize it with various materials such as cement, fly ash,nanolime, nanobauxite, nanosilica, bentonite and kaolinite in different percentages and calculated the collapse potential for all of stabilized soil with different values and compare together. Test results show that cement, nanolime and nanosilica have the most influence for reduction of collapse potential and other materials couldn't have the great role on prevention of collapse. In order to assess the collapsible behavior, several filter paper and Oedometer tests under constant vertical stress and varying matric suction in Unsaturated case for remolded soils were performed and compare. Results show that nanolime decrease the collapsible potential in unsaturated case.