Abstract: The eastern sag in Liaohe Depression bears potential oil and gas resources and is located in the Bohai Bay Basin with the Tanlu fault crossing through the Depression. In-depth investigation of strike-slip activities and their controls of structural traps will have a great significance for Cenozoic activity of northern Tanlu fault and hydrocarbon exploration in Bohai Bay Basin. In this study, Dapingfang area was taken as an example to recognize strike-slip faults and their characteristics of development on the basis of seismic data, drilling data and logging data. The study included en echelon structures in plane and their control of volcanic rock, negative flower structures in profile as well as the changes of fault dip and axial anticline along the structural strike. Rongxingtun strike-slip faults controlled and transformed Dapingfang anticline structural pattern, making strata reverse since the appearance of the second member of Dongying Formation (E₃d₂), as"lentoid". Rongxingtun strike-slip activities formed structural traps, which were character-ized by planar belt and vertical segmentation layout.