The invention discloses a novel SNR index based self-adaptive stochastic resonance rolling bearing fault diagnosis method. The method can realize fault feature extraction and fault type discriminationwithout knowing the fault characteristic frequency in advance, and can suppress the side frequency, and is not affected by external load fluctuations, the bearing rotating speed and the bearing type.At the same time, the invention also provides an effective method for extracting fault feature information and discriminating the fault type in the case of a small-scale fault feature frequency oscillation caused by a load variation or the like.