Abstract: Paleogene system in Bohai sea area has widely developed a delta sedimentary system, and the delta sand body is an important oil and gas exploration target. The seismic response characteristics analysis of delta sand body and the fine delineation of boundary is helpful to improve the accuracy of reservoir prediction in the delta. Based on the actual seismic data of Liaodong bay exploration area in Bohai sea, the physical model and parameters are designed and simplified. The physical model of typical delta sedimentation model was made, including 11 sets of sand bodies in low system domain, lacustrine system domain and high stand system domain. Under laboratory conditions, the physical simulated 3D seismic data volume was collected, processed and interpreted, and then the boundary of sand body was identified by conventional amplitude slicing and spectral decomposition techniques respectively. The results show that the amplitude slice is more sensitive to the lateral lithologic changes of the sand body, while the spectral decomposition technique can accurately depict the contour and boundary of the sand body.