The three laws are respectively Public International Law, Private International Law and International Economic Law.
 1. Public International Law refers to the general name of legally binding principles, rules and systems formed in international exchanges to adjust international relations (mainly inter state relations).
 2. In the case of differences between civil law and commercial law in countries around the world, the Private International Law addresses which country's laws should be applied to civil law and commercial law relationships involving foreign factors.
 3. International Economic Law refers to the adjustment between countries; Between international organizations; Between countries and international organizations; Between the state and private individuals in other countries; The general term of the legal norms governing the mutual economic relations between international organizations and individuals, as well as between individuals of different nationalities.
 Legal basis
 Article 467 of the Civil Code of the People's Republic of China [Application of law to unnamed contracts and foreign-related contracts] For contracts not expressly stipulated in this Law or other laws, the provisions of the General Principles of this Part shall apply, and the provisions of this Part or other laws that are most similar to contracts may be referred to.
 The laws of the People's Republic of China shall apply to contracts for Chinese foreign equity joint ventures, Chinese foreign contractual joint ventures and Chinese foreign cooperative exploration and development of natural resources performed within the territory of the People's Republic of China.