We proposed a depth-depth-matching algorithm as a fast motion transcription algorithm from a real liver to a virtual liver in a surgical navigation. The real is always captured by 3D depth camera, and the virtual is represented by a polyhedron with STL format via DICOM captured by MRI/CT. In our algorithm, we firstly compare a 2D depth image in a real world and the Z-buffer in a virtual world, and secondly search 3 translation and 3 rotation movements by matching both depth images in order for a virtual liver to move against a real liver. In this paper, the performance of our algorithm is ascertained in a PC simulation by changing several parameters and/or the evaluation function.