Abstract: In order to solve the transition problem of railway 12306 Internet ticketing and reservation system from IPv4 to IPv6, based on the network and application status of the system, this article studied and put forward the evolution scheme of railway 12306 Internet ticketing and reservation system IPv6. Based on the analysis of the national standards and plans for IPv6 evolution, starting with the characteristics of dual-stack technology, tunnel technology and address translation technology in IPv6 evolution, the article presented a technical scheme for the deployment of dual stacks and NAT address translation supplement for 12306 system, and elaborated on the transformation content, implementation steps and key issues of system evolution. The scheme has the effect of gradual evolution and investment saving.