Oil reservoir model optimization method for AVO trace gather analysis

The invention relates to an oil reservoir model optimization method for AVO (Amplitude Variation with Offset) trace gather analysis. The method comprises the following steps of: building an oil reservoir model; calibrating a rock physical model; building nonlinear relationship between earthquake response parameters and rock parameters; using the calibrated rock physical model to calculate the longitudinal wave velocity, the transverse wave velocity and the density of the oil reservoir model; then, multiplying the longitudinal wave velocity and the density to obtain the analysis impedance; using logging information to determine the upper and lower boundaries of the oil reservoir model, the wavelets and the seismic forward modeling angle range and angle interval; and generating an AVO pre-stacking trace gather trace result. The oil reservoir model optimization method has the advantages that the basis is provided for the geologic model modification; the oil reservoir model most similar to the actual underground condition can be obtained; and the oil reservoir development is facilitated.