On the slope areas of the eastern and western sides of Damintun basin in the Liaohe oilfield, the underground structure is complex, and the dip angle is rather steep. The migration location effect cannot be satisfactorily obtained by prestack time migration. The authors used the prestack time migration method adapted to this region and also studied the selection means for migration parameters, such as the construction of the migration velocity model and the choice of migration apertures and dip angles. The results are fairly satisfactory.