The application of the matched filtering technology to the separation of the deep source field from the shallow source field has been widely used in the processing of gravity and magnetic data. Based on Green's equivalent layer principle, the authors designed a multi-layer Green's equivalent layer model, and then performed fine linear fitting for radial average logarithmic power spectrum, thus realizing the separation of the deep source field from the shallow source field. The comparative analysis of the theoretical model and the practical data shows that this method is simple and practical. It can separate the deep source field from the shallow source field rapidly and effectively in large-area aerial gravity measurement, and can provide important reference basis for the study of the gravity anomaly characteristics and deep structure features, the division of geotectonic units and the determination of the strike of the faulted zone and the geological structure.