Abstract: Abstract： For aero-engine operating systems with multiple performance degradation modes， a reliability confidence evaluation method based on random correlation is proposed considering individual differences and different strength correlations. The Wiener random process and Gamma random process with random effects were used to describe the performance degradation failure processes respectively. The Copula function of the randomization of relevant parameters was used to model the degree of dependence of multiple performance parameters. An analytical expression of the boundary point of the confidence interval based on the Clayton Copula function model is derived， and an overall reliability evaluation model is established by using the edge function inference method to estimate the unknown parameters in the model through two-step optimization. Combined with the performance degradation data of aero-engine EGTM and ZVB2R， the overall reliability model was established， and the comprehensive evaluation was completed. The life interval was obtained as（1.033×104，1.278×104） cycles. The feasibility and accuracy of the model were verified by an example.

Key words: Key words： multivariate degradation, random process, Copula function, random correlation, confidence interval