Abstract: The hydrocarbon reservoir of Es4 in Wang 73 area is dominated by lithologic reservoir and structural-lithologic reservoir. The beach-dam sandstone of offshore lake facies is the main accumulation unit with the lithology being calcareous and argillaceous siltstone. The great horizontal change of the reservoir and the wide distribution of limestone in surrounding rocks decrease the difference in velocity between sand and shale, which, in turn, makes the traditional sparse impulse inversion and model-based inversion not effective in the reservoir prediction. Therefore, petrophysics is used to analyze the relationship among seismic attributes and lithology, physical property, hydrocarbon property. Then, the seismic attribute technology is used to extract root-mean-square amplitude, moveout, and instantaneous phase coherent property, which are sensitive in portraying the boundary of sand and fan body; at the same time, the distribution of reservoir is described, and the potential zone of hydrocarbon exploration predicted. Finally, well-seismic-based ex-drifting kriging technology was applied to estimate the thickness of Chunxia 2 sand set of Es4 upper member in Wang 73 area. In terms of the predicted results, one drilling well was deployed in the potential zone and the drilled thickness of Chunxia 2 sand set is coincide with the predicted thickness.