Abstract: The peak value of stress response is importantwhen the strength of the structure in broadband random vibrations isconsidered. Based on the peak value equivalent theory of the randomvibration and the sinusoidal vibration, the peak value of stressresponse in arandom vibration can be obtained by the stress response at the resonant frequency of the sinusoidal vibration. The modal analysis,frequency response, prediction for the acceleration response and the peakvalue of stress response of a selected structure in random vibrationsare carried out with MSC.NASTRAN. It is shownthat the error of the peak value of stress response between analysisand test results is less than 10\%; therefore, the method ofstress response prediction in random vibrations is reasonableand practical.