The dynamic response of cultural showcases under seismic and simple harmonic excitation is described in this paper. The upper limit of the acceleration magnification coefficient of the booth surface was determined for the fixed and floating showcases. First, the vibration experiments according to 1∶1/0.39 of a museum exhibition shelves were carried out to obtain the amplification coefficient of the surface of the showcase booth under two kinds of boundary conditions. The simulated results were compared with the experimental data to verify the correctness of the finite element model and analysis method. Second, the finite element model of the prototype was established in order to consider the influence of the excitation amplitude and excitation frequency on the amplification coefficient of the five sizes of showcases. These research results will help to direct the work for protection of cultural relics.