This thesis analyses soil-structure interaction for different foundation mat thicknesses, soil properties and subgrade models. Dimensions of foundation mat, loads and load combinations were determined based on Eurocode standards. Mat thicknesses of 25, 40, 55, 70 and 100 cm were analyzed for two characteristic types of soil: soil with a higher load-bearing capacity, for which an average settlement of 1 cm was assumed and soil with lower load-bearing capacity, for which an average settlement of 10 cm was assumed. Three different subgrade models were used: two different two-dimensional singleparameter mechanical models (Winkler´s hypothesis with constant coefficient of subgrade reaction model and a pseudo-coupled concept model) and a three-dimensional subgrade model, where the stress and strain conditions in the soil are more accurately modeled. Finite element method was used for all analyzed cases using SAP200 and Plaxis 3D computer programs. By comparing the results, the distribution of settlements, internal forces in the structure and the influence of different soil properties and subgrade models were analyzed. The comparisons show that results for a two-dimensional singleparameter mechanical subgrade model with constant coefficient of subgrade reaction differ substantially from the three-dimensional subgrade model results, whereas the results using a pseudo-coupled concept are comparable to the results from a full three-dimensional subgrade model.