The stationary gaussian hypothesis is usually used to estimate the vibration fatigue life of structures. However, in actual engineering, the dynamic response of the structure usually exhibits non-stationary and non-gaussian, especially under harsh working condition or changing environment. The structural vibration fatigue life is closely related to the dynamic response characteristics, especially with respect to the structural response kurtosis used to characterize the non-Gaussian characteristics. In this paper, the influence of non-stationary and non-Gaussian random excitation on structural response kurtosis was studied by means of simulation and experiment. Firstly, by the means of simulating, the transmission law of excitation-response kurtosis was studied from three aspects, including system damping ratio, excitation frequency bandwidth, and excitation non-stationary characteristics. Then, the response kurtosis law was verified by the test results of cantilever vibration stress response. The results show that when the excitation is a stationary gaussian random load, the damping ratio and the excitation frequency bandwidth have no effect on the response kurtosis, and the response is approximately Gaussian distribution. When the excitation is stationary non-gaussian and non-stationary non-gaussian random load, if the damping ratio of the system is large, the response kurtosis is mainly affected by the damping ratio; If the damping ratio of the system is small, the frequency bandwidth and non-stationarity of the excitation have significant effects on the response kurtosis. The research results can provide support for predicting the vibration response and fatigue life of engineering structures under complex non-stationary non-gaussian random loads.