From the origin, there has been a strong connection between international relations and international law. In the development of the history of different academic subjects, the research on international relations and international law are interdependently promoting each other. As a result, the realization of interdisciplinary research on international legal theory and the study of international law is inevitable. As a matter of fact, even though the interdisciplinary research of the two subjects has been separated for almost half a century, the need for the development of the subject and the changing world political and economical status give them a new chance for reunification. Recently, the interdisciplinary research on international relations theory and international law by the Western academic is becoming the order of the day, which has become the latest shining point of the recent development of the two subjects, which is even regarded as the new revolution of international relations theory and the study of international law. In this context, the past ten years is a period of emergence of Chinese international relations and the interdisciplinary research of international law. In the past ten years, some scholars have overcome “the difficulty of interdisciplinary research,” “the prejudice within the subject” and “the gap among different subjects,” and made pioneering research in the field of “systematic connection” and “issues in overlapping field.” Moreover, they gradually make the interdisciplinary research to be a popular method and a common recognition. Based on the current studies, interdisciplinary research will have a broad future in the fields such as “the interchange of concepts,” “the exchange of method,” and “the mutual assistance of materials,” which will provide scholars in this area with a broad space for research.
After the Cold War and the quick development of globalization, non-state acts by international organizations, transnational corporations and nongovernmental organizations (NGOs), etc., are becoming more active. Global issues with regard to, inter alia, environment, human rights, terrorism are constantly emerging, which bring great challenge to the Westphalia System that is based on state sovereignty and centered on the national state. At the same time, the values, which include “individualism” and “global justice,” are constantly casting impact on international legal system. Doubtlessly, in the current context of international relations, “justice among states” is still the reasonable positioning of the value of modern international law. However, making “individualism” and “global justice” compatible and modifying “justice among states” is an inevitable trend. At the same time, the rule brought about by the modification on the value of justice must be handled properly.