Abstract: Digital watermarking technology has provided a copyright protection for 3D
models at the network. The characteristics, classifications of the digital watermarks for 3D models
and the techniques of attack to them are briefly illustrated. The present studies and functional
evaluation of watermarks of all kinds including point clouds model, mesh model, parametric
surface model and body data model are analyzed. The difficulties and matters of 3D model
watermarking which need further study are finally concluded.

Key words: 3D model, copyright protection, digital watermark, functional evaluation