The issue of bearing capacity and settlement were the topics of interest for geotechnical researchers. In this regard, methods and techniques for soil improvement have been devised and developed to increase the load capacity and to reduce settlements. In this study, the soil bearing capacity improvement investigated by using Geobags. Today, Geobog has been widely used in geotechnical engineering, especially in increasing load bearing capacity. Geobags are usually made from high tensile strength geotextiles. Geobags are filled with materials such as gravel, sand, and even construction wastes, and the span is sewn and placed in the spot. Geobags can be used as flood protection and bridge protector, while increase soil bearing capacity and reduce settlement and vibration. In this study, The bearing capacities of shallow foundations on reinforced and unreinforced trench under vertical loads are determined experimentally and numerically. For this purpose, Geobags filled with construction waste were placed in sandy soil and then loaded. Consequently, using force-settlement diagrams, the effect of soil improvement with Geobog has been investigated. In the next step, the experimental conditions were modeled by using the finite element method (ABAQUS software) and the results of numerical analyses were validated. After validating the numerical modeling, the effect of Geobog dimension on soil improvement was studied and a relationship was defined. The results of this study showed that Geobag increases bearing capacity 2 to 4 times compared to the neat soil. In addition, the effect of Geobog number along the width of the plate was investigated. The results showed that the division of Geobags in the limited number has no effect on the load capacity. Also, the effect of Geobog number on the width of the plate was investigated. The results showed that decrease of modulus elasticity of Geobag has no effect on the load capacity; Which may be to the greater effect of enclosing the soil inside the bag on the bearing capacity and the insignificant impact of the soil and bag interaction angle on bearing capacity. Finally, stress and strain contours in Geobag and soil and the failure under the foundation were studied. Key Words Geobag, Bearing Capacity, Numerical Modeling, Trench