Based on the principle of structural dynamics and the basic theory of the finite element method, the finite element analysis software SAP2000 was used to establish an analytical model for an actual frame structure base isolation building and a similar non-isolated building, respectively. The dynamic time history analysis method was applied to analyze the horizontal seismic responses of the two models. The results showed that the horizontal seismic response of the base-isolated building was much smaller than that of the non-isolated building, and the natural period of the superstructure of the base-isolated building was significantly larger than that of the non-isolated building. Moreover, the interstory shear force, basement shear force, and the relative displacement and acceleration of the floor were lower than those of the non-isolated building. In general, isolation bearings can significantly reduce the adverse effects of horizontal ground motion on a structure and thus deserve propagation.