Abstract: Some deficiencies existed in the traditional deterministic stress and fatigue analysis of gas turbine disk,for example,it cannot quantify the influence of discrepancies in the structure design variables.The stress-strength interference method and Fuzzy Probability Integral (FPI) method,which can quantify these discrepancies,were applied to evaluate the structure reliability of the turbine disk.Result shows FPI method is rapid and effective.The influence of approximations existing in the interference method was also studied.At the end FPI method was used to evaluate the whole disk reliability distribution.This result is helpful not only for understanding the reliability level of the whole disk but also for the further design of the disk.