We investigate the influence of soil-structure interaction on the analysis and design of a 6-storey reinforced concrete structure building and basement. We consider models that simulate two different conditions: namely, soil-structure interaction and fixed base behavior. The influence of the interaction of the soil structure on the dynamic behavior of the structure is reflected in an increase in the vibration period, as well as an increase in the damping of the system compared to the fixed base model, which does not consider the support floor. The influence of soil-structure interaction on the seismic design of the structure is reflected in a decrease in horizontal spectral acceleration values. Soil inclusion in the structural analysis provides results, voltage and displacement values, which are closer to the actual behavior of the structure than those provided by the analysis of a fixed base structure.