Abstract: The reservoir prediction technique based on seismic inversion plays an important role in the exploration of Xihu Sag. The quality of primary data, such as seismic data, well logs is the key to the quality of seismic inversion. However, limited by the geology conditions and drilling technique, the borehole enlargement often occurs during drilling, which makes the sonic and density curve distortion. Therefore, it is necessary to conduct environmental calibration before inversion. Based on the analysis of the relationship between the sonic, density curves and other curves such as Gamma Ray, neutron porosity, a multi-parameter simulation calibration method is established. The calibration rationality is verified, and the quality of well-seismic correlation and seismic inversion are improved after applications of the calibrated curves, which proved that this method is effective.