Abstract: The vertical displacement of boundary faults along strike during different geologic stages was studied using seismic data as well as tectonic and stratigraphic thickness maps for the Xinanzhuang Fault in the Nanpu Sag of the Bohai Bay Basin. The segmentation and evolution of boundary faults were studied and their controls on sediments were analyzed. During the deposition of the third member of Shahejie Formation, the Xinanzhuang Fault was divided into three individual fault segments from east to west, and relay ramps developed where fault segments overlapped. When the first member of Shahejie Formation was deposited, these individual fault segments were linked, and the fault segment to the north of Gaoliu Fault began to be abandoned. At the end of Dongying period, a unified fault was formed, yet still showed segmentation features. Some transverse folds appeared on hanging wall. The fault segment to the north of Gaoliu Fault was abandoned. Coarse sediments migrated into the basin through transverse folds and relay ramps, resulting in favorable reservoir development.