With the development of blockchain technology, various kinds of blockchain projects with different characteristics and adapting to different application scenarios have emerged. However, different chains cannot be interconnected, forming many value islands, restricting the promotion and ecological development of blockchain. Cross-chain technology is an important technical means to achieve interconnection between different chains, improve performance, and expand the scope of application; combined with the advantages of nodes and state control in the licensing environment, this article mainly studies the cross-chain technology of licensed public chains.