Abstract: As a new soft soil foundation treatment technology, the geosynthetics-bound stone columns (GBSC) is widely used in engineering. The bearing capacity of GBSC is determined by the tensile strength of the geosynthetics and the property of the soil layer. The interaction mechanism of geosynthetic materials, stone columns and foundation soil is analyzed, The method for calculating the strength of GBSC is proposed considering the contribution of the constraint tension of geosynthetic materials and soil confining pressure, and then the method for the ultimate bearing capacity of GBSC is deduced in which the strength of GBSC and the action of the upper load are considered. A computer program is compiled to calculate the limit bearing capacity and tensile force of geosynthetic materials along the depth. An calculation example illustrates the required parameters and the calculation process. The achievement can be used for the bearing capacity design of geosynthetics-restrained stone columns.