The main network of colleges and universities is also generally based on IPv4, but due to the limitations of IPv4 protocol, the Internet has been gradually transitioning to IPv6. The promotion of IPv6 carried by education network in China has also lasted for more than ten years. Due to technology, application, market and other reasons, IPv6's replacement for IPv4 is not smooth. It is slow to promote at the operator level, and the resources of colleges and universities are not rich, especially in higher vocational colleges. This paper introduces the practical experience of IPv6 in the construction and promotion of higher vocational colleges, and solves the problems of compatibility, application service and nterconnection in the process of IPv6 network construction. It involves pure IPv6 test network, tunnel docking, NAT-PT and other technical schemes, aiming to ensure the stable operation of the existing IPv4 network, and gradually transition to pure IPv6 network.