As a special system in private international law, proof of foreign law is the basis for the accurate trial of foreign civil and commercial cases in the process of the construction of the Belt and Road Initiative, and also a prerequisite for the proper application of foreign law. The setting and judicial practice of this system play the important role in the legal and reasonable settlement of foreign civil and commercial disputes, the overall promotion of the credibility of judicial trial, and the formation of sound environment for international civil and commercial exchanges in China. At present, there is a tendency towards decentralization and fragmentation for the mechanism of proof of foreign law in China, such as a lack of clarity, concreteness and operability, which has obviously failed to meet practical needs. Therefore, under the Belt and Road Initiative, China should properly integrate and coordinate the legislation on the mechanism of proof of foreign law, further refine the subject of liabilities, suggest that the accuracy of proof of foreign law provided by the parties and the civil professional institution depends on the discretion of the judge, so the parties and the institution has no liability for authenticity or legitimacy on proof, expand the way to identify foreign law actively, increase terms specifically for proof of foreign law in bilateral judicial assistance agreements, set up more centers for proof of foreign law timely, define that there is no necessary to limit the way of proof in legislation. Overall, China should take related measures in more aspects to enhance the international influence and credibility of the nations’ judiciary.