Background and Aim: The principle of good faith appears in various dimensions after the conclusion of international treaties. By accepting this principle in different legal systems, ideas based on altruism are evolving in the international arena. Interpretation will be useful when it is legal and limited and consistent with the plain meaning of the words and the context of the treaty. The purpose of this research is to explain the role of good faith in the interpretation of international treaties.
Materials and Methods: The research method is descriptive and analytical using library resources.
Ethical Considerations: In the upcoming research, it has been carried out by maintaining the originality of the content and respecting the principle of fairness and trustworthiness.
Findings: In this research, it is observed that although the principle of good faith by imposing some requirements on the parties to the treaty, provides the possibility of expanding the scope and content of the obligations of the treaty, but this concept allows the court to introduce obligations beyond the obligations known in that category. It does not give the treaties.
Conclusion: In this treaty, good faith takes care from within, while justice from outside and from a higher position oversees its faithful execution. The treaty supervises its correct and honest implementation, but justice has the queen of piety, which makes the commitment of the parties to be fulfilled, because it requires piety before any commitment, which piety prevents non-fulfillment of commitments.