Introduction: Justice and fairness are two basic moral concepts in law. All judges, in the performance of their judicial duties, have faced the demands of issuing "just" and "fair" verdicts many times, without perhaps paying attention to the meanings of justice and fairness. Therefore, in the present study, the place of fairness in fair proceedings has been examined. Materials and Methods: The current review is descriptive and analytical and based on a library study. Conclusion: The rule of fairness, which is the purpose of this research, means considering the circumstances and conditions of the case and involving them in giving the appropriate decision. In the Roman, Germanic and Common law legal systems, fairness is a concept that entered these systems from the past and means a decision based on the judge's conscience. In the common law system, equity is one of the sources of rights; However, fairness is not stated as a rule in Iranian law, and some jurists have proposed it as a source of law that is not written. On the other hand, this concept also has the characteristics of a legal rule and has many applications in law, so it can also be a legal rule