Technology of network and mobility are two major present communication technologies. With the rapid development of the technology of network and portable terminal, it becomes more and more important in the network for the realization of the support to mobility. IPv6, which is taken as the next generation of Internet protocols, is put forward to replace the current Internet protocol IPv4. One of its new characteristics is to support the mobility. Firstly, compares IPv6 with IPv4, and points out primary technique improvement over IPv4. Secondly, expounds that IPv6 can support mobility, and some key techniques is introduced. Lastly it can provide users mobile service with multi-access in mobile stage, it offers much convenience to the solution of mobility with its rich functions.