Although the phase-shift seismic processing method has characteristics of high accuracy,good stability,high efficiency,and high-dip imaging,it is not able to adapt to strong lateral velocity variation.To overcome this defect,a finite-difference method in the frequency-space domain is introduced in the migration process,because it can adapt to strong lateral velocity variation and the coefficient is optimized by a hybrid genetic and simulated annealing algorithm.The two measures improve the precision of the approximation dispersion equation.Thus,the imaging effect is improved for areas of high-dip structure and strong lateral velocity variation.The migration imaging of a 2-D SEG/EAGE salt dome model proves that a better imaging effect in these areas is achieved by optimized phase-shift migration operator plus a finite-difference method based on a hybrid genetic and simulated annealing algorithm.The method proposed in this paper is better than conventional methods in imaging of areas of high-dip angle and strong lateral velocity variation.