In this study, the vertical stress values occurred under the center line of the uniformly loaded square footings were investigated experimentally and numerically. The results of the study were compared with the results of Boussinesq method. Tests were performed in a square shaped test box and pressure transducer was used to measure the stresses. In the numerical analysis, soil was modeled using finite element method with two dimensional axi-symmetric and three dimensional conditions as linear elastic and non-linear elasto-plastic materials and the effect of these models on the vertical stress values was investigated. Finally, a general agreement was observed between the experimental, numerical and theoretical results for the values obtained for predetermined depths of sand and the obtained results are discussed.