Abstract: In this paper, we calculated the depth of the upper and lower boundaries of the Paleogene for Liao Dong Bay Depression based on the newly acquired gravity data. Residual thickness of the Paleogene and its distribution pattern are analyzed and studied with the results. The research results show that the Paleogene is partly missed on the Liaodong bulge to the west of the fault F1. The data also shows that the residual thickness of the Paleogene is unevenly distributed in different tectonic units, showing a pattern of “ thick-thin-thick-thin-thick” trend on plane view, while the Liaozhong Sag remains the sedimentation center of this area.