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As to the sonic fatigue problem of an acro-cngine combustor liner structure undcr the random a- coustic loadings,an cffective method for predicting the fatigue life of a structure undcr random loadings was studicd.Firstly,the probability distribution of Von Mises strcss of thin-wallcd structure undcr random loadings was studicd,analysis suggestcd that probability density function of Von Miscs stress proccss accord approximately with two-paramctcr Weibull distribution.The formula for calculating Weibull parameters were givcn.Based on the Miner linear theory,the method for predicting the random sonic fatigue life bascd on the stress probability dcnsity was developed,and the model for fatiguc life prediction was constructcd.As an cxamplc,an acro-cngine combustor lincr structure was considercd.The powcr spcctrum dcnsity (PSD) of the vibrational stress response was calculated by using the coupled FEM/BEM (finite clemcnt method/boundary elcmcnt mcthod) model,the fatiguc life was cstimated by using the constructed model.And considcring the influence of the wide frequency band,the calculated results were modified.Comparetive analysis shows that the es-timated results of sonic fatiguc of the combustor liner structure by using Weibull distribution of Von Mises strcss are more conservative than using Dirlik distribution to some extend.The rcsults show that the mcthods prcscntcd in this papcr are practical for the random fatigue life analysis of the acronautical thin-wallcd struc-turcs.