Collapsible soil is a great challenge for geotechnical engineers because it shows a good strength when dry but after inundation it loses its strength and shows a considerable collapse settlement. Several techniques for improving collapsible soil have been proposed in previous studies such as compaction, replacement, prewetting, in addition to chemical additives . In this study Geosynthetic (Geotextile and Geogrid) materials were used as a soil reinforcement of collapsible soil, and the effect of soil reinforcement on the behavior of collapsible soil and the value of collapse settlement was investigated. Experimental tests were carried out using isolated square footing model resting on homogeneous or partially replaced collapsible soil which was subjected to inundation due to rain fall water. The collapse settlement beneath the isolated square footing model was measured in case of natural collapsible soil and improved collapsible soil either with using replacement layer only or using reinforced replacement layer. The recorded results are presented to evaluate the validity and efficiency of using such technique for improving the collapsible soil. The next stage of this study is to perform a field study for the same purpose and compare results with the experimental investigations.