Abstract：The stack of converted waves from slant interface is terribly complicated. Coor- dinates for the conversion points of converted waves depend on both the dip angle and dip direction of a slant interface. Conversion points must be located in order to make common conversion point gathering and stacking of converted waves from the slant interface. The coordinates of conversion point is the function of offset,normal distance from source to the interface,ratio between S-wave'velocity and P-wave ve- locity and the dip angle of the interface. Two equations，namely a quadruplicate equation and an iteration equation,are deduced,which are used to determine conver- sion points in the slant interface. The influence of interface dip,angle upon conver- sion point is discussed also. Calculation result shows that conversion point can be well located using the iteration equation.
