The invention discloses a seismic wave low-frequency energy change rate extraction method based on variational mode decomposition, and belongs to the field of oil and gas geophysical reservoir detection, and the method comprises the steps: firstly carrying out the variational mode decomposition of a seismic wave signal, and obtaining a mode component; secondly, performing improved generalized S transformation calculation on each modal component to obtain a time-frequency diagram; thirdly, extracting a spectrogram from the time-frequency diagram, and fitting linear parameters in a low-frequencyband by using a least square method; and finally, performing weighted average on the slope of each modal component fitting linear parameter to obtain a low-frequency energy change rate. Compared withthe prior art, the method has the advantages that compared with a traditional high-frequency band attenuation gradient method, the change of low-frequency band energy contains more oil and gas reservoir information, a rock physical basis is provided, and reservoir characteristics can be reflected more accurately.