In this paper, we first introduce a 3D morphing method for landmark-based volume deformation, using various scattered data interpolation schemes. Qualitative and speed comparisons are also made for different interpolation schemes. To efficiently render the volume morphing process, a new deformable volume rendering algorithm is presented. The algorithm renders the deformed volume directly without going through the expensive volume construction process. Piecewise linear approximation of the deformation function by adaptive space subdivision and template-based block projection are used to speed up the rendering process. While the resultant timings is slower than real time, it is much faster than existing volume morphing/rendering pipelines.