Surrogacy technology provides the possibility for families who are unable to have children. Different countries have different legal regulations on surrogacy, which leads to the creation of transnational surrogacy, and at the same time, disputes over transnational surrogacy are also increasing. As we all know, surrogacy is contrary to the public moral order in China, which leads to the issue of public order retention.Private international law, as an important legal system in the field of International law, has an unshakable position and role in dealing with transnational surrogacy disputes. In transnational surrogacy disputes, public order is mainly reflected in the legal regulations of each country on surrogacy, the determination of paternity and the relevant regulations on the ethics of surrogacy, and its role is mainly reflected in the exclusion of the application of foreign laws and the refusal to recognize the judgments of foreign courts. In the application of the law, countries have tried to find a balance between the recognition of foreign judgments and the protection of the public order of the courts. This article will take a comparative and case study approach, using the issue of surrogacy as an entry point to explore the application of public order reservations in this particular area.