The invention discloses a bearing fault detection method based on a variable learning rate multi-layer perceptron. The method comprises the following steps: Step 1, collecting and extracting a vibration signal of a bearing by using a sensor; step 2, carrying out feature iteration on the vibration signal by using a multilayer perceptron; 3, a back propagation process is used for automatically optimizing the weight coefficient of the multi-layer perceptron, the learning rate of automatic optimization is changed according to the number of iterations, time domain signals obtained after iteration enter a support vector machine classifier, and a diagnosis model is obtained; step 4, inputting test data into the diagnosis model for diagnosis, and completing the detection of the bearing fault; according to the method, the bearing signal faults are extracted in a crossed mode through the multi-layer perceptron based on the variable learning rate, the loss function value can be rapidly reduced to complete fault diagnosis, the feature extraction speed is high, data do not need to be preprocessed, diagnosis precision is high, and the method has the advantages of being rapid in feature extraction, high in precision and good in robustness.