Abstract: For the geological property of Xihu Trough Area in the East China Sea, density and sound wave in the logging data is used to set up the wave impedance curve. When the density and sound wave were fuzzy because of enlarged well, we can utilize the gamma-ray and relative depth to adjust them. According to statistic data, it is rule that the value of wave impedance of shale is more than sandstone, and the value of wave impedance of water-bearing sandstone is more than oil-bearing sandstone in the near depth.