Chongqing is the earliest city in inland China to open China-Europe Express Train and is also the central city of the International Land and Maritime Trade Corridor. Since the proposal of the Belt and Road Initiative，Chongqing has made new achievements in the trade with Europe， but also exposed some problems. The operation efficiency of China-Europe Express Train needs to be improved，and some local enterprises have encountered trade protectionism and trade barriers in international trade. International Law can provide a solid foundation for trade with Europe. China should promote the legalization of trade rules and transportation rules under the framework of “B&R”， solidify the rights and obligations of both sides with international law， and protect the interests of all parties. Relying on the Belt and Road Initiative， Chongqing should build a good transportation hub for China-Europe Express Train and New International Land and Maritime Trade Corridor. At the same time， Chongqing should find a suitable development road according to the characteristics of local enterprises， enhance the international influence of Chongqing and China，and promote the construction of “B&R”.