The source-grid-load collaborative interaction and the precision regulation of adjustable resources with high sensitivity provide important support for improving the regulation ability and efficiency of new power system, and promoting the efficient and reliable operation of new power system. Therefore, precision regulation method for source-grid-load collaborative interaction considering power node and resource sensitivity is proposed in this paper. Firstly, from the two perspectives of power grid application requirements and node adjustable resources, the overall idea of double-layer sensitivity analysis method is described, and the layered logic architecture of the precision regulation platform for regional source-grid-load collaborative interaction is constructed, in order to realize and apply the proposed double-layer sensitivity model and precision regulation method. Secondly, the first layer power branch sensitivity analysis model is proposed for the power grid side to obtain the power branch sensitivity matrix. A fine-grained second layer adjustable resources sensitivity analysis model is further established for the diversified adjustable resources aggregated under the power node to complete the quantitative ranking of adjustable resources regulation sensitivity. Then, the application process of double-layer sensitivity analysis results is designed in detail. The regulation sequence and regulation quantity of source and load are defined. Finally, taking a power system as an example, the effectiveness and rationality of the proposed model and method are verified. The results indicate that the proposed precision regulation method can accurately select high sensitivity power nodes and effectively sort high sensitivity adjustable resources when solving the multiple scenarios application needs of power grids.