By employing Green，s function，the principle and pattern of biharmonic spline interpolation are studˉied，and the formulas of one tomultiple dimensional biharmonic spline interpolation are deduced.One feature of this algorithm is itsm inimal filter curvature.On a basis of applying the biharmonic spline interpolation，a converˉgence algorithm ofgrid node value is used to approximate the gridˉnode values to their surrounded values at logˉging structure data，and to make the separate logging structure data in every well impact and change adjacent seism ic structure data in a certain way，therefore resulting in an integration of logging and seism ic data. The effect of this biharmonic spline interpolation has been verified by its application in the typical complex reservoir in Yongˉ3faulted block，Shengli oilfield.The application results indicated that the structuralmaps proˉduced by thismethod on a basis of3D seism ic data with high precision can well avoid m istakes in the structural mapswith lower resolution produced by only using logging data，due to higher resolution of the formermaps.This method of biharmonic spline interpolation can effectively integrate seism ic data with logging data in predicting stratigraphicˉstructural surfaces，and elim inate the uncertainties resulter from using a single type of data，thus making the prediction more accurate and reliable.