Compacted sandy-conglomerates with giant-thickness develop widely in the northern steep slope of Dongying sag, which are multiepisodically superimposed vertically and distributed as a skirt-shape horizontally. Fan bodies are characterized by narrow facies distribution, rapidly changed physical properties, low permeability and porosity and complicated geophysical responses. More than 100 core samples are selected and analyzed by ultrasound. Based on the analysis of the test data and experimental results, we conclude that the main factors which influence the seismic velocity of sandy conglomeratic body are lithology, porosity, pore structure and lime content. While different fluids are saturated in the rocks ,it has less effect on P-wave velocity. The elastic modulus of dry core samples is different from that of the rocks saturated with oil and water. The difference of petrophysical parameters between samples saturated with oil and water is almost indiscernible. These test and results lay a foundation for the selection of sensitive seismic attributes of sandy-conglomerate.