In order to investigate the fatigue characteristics of an airborne module under random vibration loading,the general expression of structural vibration fatigue life is derived,based on the power spectral density function,which is simplified by Gaussian three interval method,the effect of random signal clipping in vibration test on stress amplitude probability distribution is also considered. Then,we analyze the relationship between the structural vibration fatigue damage and vibration modal which can be used to obtain the dynamic response of the crucial fatigue point under the given vibration loading. Finally,the vibration fatigue life of the module is given. It is shown that the numerical results coincide well with the experimental data.