For estimating long storage life and reliability index of some microwave electronic product,weak link and sensitive stress of product were found by the reliability analysis methods.A modified reliability enhancement testing(RET) was used for finding out stress limits and analyzing performance index change.The tested results show that RET can either determine safe range for accelerated life testing(ALT) and accelerated degradation testing(ADT) or be used to select key performance index for ADT to provide an accelerated testing method with safe acceleration range.