Abstract:his paper propose a new algorithm to hide information in part vertices of a 3D triangle mesh to improve the security. The algorithm first use the PCA method to analysis the 3D model and establish a unique vertex sequence. After that, to compute a seed from the mesh for the pseudorandom number generator called Mersenne twister. With the same seed, pseudorandom number generator will produce the same pseudorandom list. Than,to pick part vertices for hiding by using the pseudorandom list to index the vertex sequence. This steganography method effective reduce the accuracy of the steganalysis algorithm.