An important problem encountered by foundation engineers involves partially saturated soils which possess considerable in-situ dry strength that is largely lost when the soils become wetted. It goes through a radical rearrangement of particles and a large loss of volume upon wetting with or without additional loading. Increasing moisture causes chemical or physical bonds between the soil particles to weaken, allowing the structure of the soil to collapse and the ground surface to subside. The most significant parameters governing collapse of partially saturated soils are the initial dry density, moisture content, degree of saturation and overburden pressure. The behavior and performance of a shallow foundation rests on compacted sand replacement over treated collapsible soil by pre-wetting and compaction is investigated in the current study. Experimental work program was developed to explore the effect of thickness of compacted sand replacement on collapsibility potential. Treated collapsible soil was replaced with imported cohesion-less soil with variable thickness up to footing width. Replacement soil increases the rate and reduces the amount of footing settlement and increases bearing capacity by a factor of 1.80 under concentric loads for cases under study. For compacted collapsible soils, partial replacement by compacted sand layers decreases collapsibility potential risk.