[Objective] The spatial patterns of urban rainwater were explored, and the network structure and temporal and spatial distribution characteristics of surface runoff of Kunming City were analyzed in order to provide a targeted planning basis for sponge city construction. [Methods] The structure and spatial pattern of a surface runoff network in the central urban area of Kunming City were quantitatively analyzed by using an established GIS database combined with the minimum cumulative resistance (MCR) model and spatial autocorrelation analysis. [Results] ① Potential surface runoff in the study area was affected by the influence of the lateral resistance and local resistance, with a total of 1 274 and a cost ratio was 0.83. Network structures were complex, and the confluence process had significant directionality. ② Runoff connectivity threshold of the sub-catchments was 19.16, and when gravity exceeded a threshold value, runoff among sub-catchments was interrupted. ③ Unit density of the runoff path decreased with increasing gravity among sub-catchments. Potential runoff distribution under six different gravity conditions all showed significant aggregation, but decreasing gradually with increasing gravity. The greater the gravity between sub-catchment areas, the more likely it is that confluence was produced. [Conclusion] The combination of the MCR model and spatial autocorrelation analysis can intuitively reflect the confluence network and distribution characteristics of surface runoff in different rainfall stages.