In this study, additional vertical stresses, which occur in a soil as a result of uniformly loaded circular foundation, resting on sandy soils unreinforced and reinforced by geogrids, have been investigated by laboratory model tests. Additional vertical stress values that occur on a horizontal planes of particular specified depths, have been measured. In the tests, pressure transducers have been used in order to measure stress values. Geogrid, which has double axis and placed into the depth of u=0,3D (u=depth of reinforcement, D=diameter of foundation) at soil, have been used in the tests. Finally, it was concluded that additional vertical stress values, which occur in a soil as a result of uniformly loaded circular foundation on a horizontal planes of particular specified depths can be decreased significantly according to the unreinforced case.