Abstract: The decentralized feature of blockchain technology provides innovative solutions to solve the core problem of lack of trust in business ecology. With the reference of "The Four-Color-Map Conjecture", this paper summarized the basic "4+1" cross-border trade blockchain application mode, as well as its extension mode, which provided a feasible and effective solution in the “Parallel-Imported Cars under Bonded Warehousing” scenario. The results demonstrates that the two models can not only build a safe and credible cross-border blockchain digital mechanism to meet the requirements of this new trade format, but also promote trade facilitation. This paper can be a valuable reference for related research of blockchain technology application and the establishment of cross-border trade mechanism.