The Internet has grown rapidly in China since 1995. The number of Internet users in China has doubled nearly every six months since, reaching 46 million up to now. Consequently, a huge volume of IP addresses is needed and imperative. On the other hand, mobile communication has been popularized in China with remarkable high speed. There are about 200 million mobile users, who would be mobile IP users potentially. Therefore, IPv6 would be a key technology and an important chance for China with a big population to obtain more needed IP addresses, and to develop applications based on mobile IP. In this paper the significance of IPv6 for China and the reason for a huge potential IT market are explained. Several IPv6 projects from 1998 to the present are introduced. The achievements of IPv6 development including test-beds, services and research are described.