Aiming at the problems of difficulty and low accuracy of mechanical fault diagnosis under the condition of small samples, a fault diagnosis method based on sgmm model was proposed. Firstly, the extraction task related to the fault modeling strategy was determined, and the change of potential mechanical fault state was estimated; The minimum entropy deconvolution result was obtained by the variational mode decomposition of the fault signal, which meeted the processing requirements of the endpoint effect and realizes the location and diagnosis of the mechanical fault. The analysis results showed that sgmm model payed more attention to the continuous detection of fault pulse components. If kurtosis was taken as the measurement standard, this method could enhance the fault impact force more effectively, and could diagnose the early fault state of bearing mechanical components earlier.