Abstract: Cage-based deformation has become a popular method for shape deformation in computer graphics and animation. To edit a shape first requires a cage to be built to envelop the target model which is a tedious work by manual approaches. In this paper, we develop an automatic method to generate the cage for a model using voxelization based decomposition. We first voxelize the input model, and then use the seed filling algorithm to group the inner voxels. By dilating the inner voxel groups, we decompose the model into broad regions and narrow regions. Then we construct partial cages using different strategies and unite them to get a cage. Experiment results demonstrate that our method is effective, efficient as well as robust to model transformation. Copyright 2014 John Wiley & Sons, Ltd.