In view of the deficiencies of peak factor,pulse factor and kurtosis factor in the monitoring of rolling bearing running condition,a new method to evaluate the variation of vibration performance of rolling bearing is proposed based on the fuzzy-set theory. Firstly,the original data sequence of the rolling bearing vibration is divided into the sample sequences,and then the intrinsic sequence is selected to calculate the standard deviation of each sample sequence and the absolute correlation degree,the gray confidence level and the closeness degree relative to the intrinsic sequence as new sample values. Then a fuzzy similarity matrix made up of these values processed in order of magnitude and by the linear mapping formula is further transformed into a fuzzy equivalence matrix via transitive closure method and the evaluation of the variation of vibration performance of rolling bearing is made by comparing equivalence coefficients in the fuzzy equivalence matrix with the set threshold（ λ = 0. 5）. Finally,the feasibility and correctness of the proposed method are verified by simulation data and experimental data.