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The 3-P(4S) parallel platform has three translational degrees of freedom and excellent decoupling performances. In order to analyze the application prospect of 3-P(4S) parallel platform as a vibration platform, first of all, the vibration model was introduced according to its dynamic model, and vibration equation was simplified according to the characteristics of the driving units. And the vibration frequencies and regular vibrations were obtained. Furthermore, the vibration model was verified by the simulation in ADAMS software, and the error was within the range of 0.5%. Besides, the vibration characteristics of the 3-P(4S) parallel platform were analyzed, including the natural frequency with the change of position and sensitivity characteristics. Finally, the modal test of the 3-P(4S) parallel platform was carried out based on the hammering method, and the modal test results were the time domain signals, and then the time domain signals were converted into frequency domain signals by Fourier transformation. The experimental results of natural frequencies were obtained by the frequency domain waveforms from the modal test, and the errors of the natural frequencies and the theory calculated ones were within the range of 3%, which proved the correctness of theoretical analysis, and indicated that the 3-P(4S) parallel platform could be applied to the fields of vibration simulation and vibration test.