Arbitration is regarded as one of the most significant private dispute resolution mechanisms in the Iranian legal system, founded upon the principles of party autonomy, procedural flexibility, expertise, and efficiency. Nevertheless, arbitral awards are not absolutely immune from legal scrutiny, and Iranian law has recognized several situations in which an arbitral award may lose its legal effect, be invalidated, or the arbitral process itself may be terminated. Among these, the concepts of “nullity of arbitral award,” “annulment of arbitral award,” and “termination of arbitration” are often used interchangeably in practice and even in some legal writings, despite their fundamental differences in nature, basis, effects, and the scope of judicial intervention.

This article adopts a descriptive-analytical method and draws upon Imami jurisprudence, Iranian civil law, the Civil Procedure Code, the International Commercial Arbitration Act, and judicial practice in order to clarify the conceptual and functional distinctions among these three institutions. The findings reveal that the nullity of an arbitral award concerns the inherent absence of essential validity requirements, producing an automatic and retroactive effect that cannot be cured by party consent or lapse of time. By contrast, annulment of an arbitral award is a judicial remedy which depends upon the filing of a legal action by an interested party and the issuance of a court judgment within the statutory time limit. Termination of arbitration, on the other hand, primarily concerns the extinction of the arbitral relationship and the end of the arbitrator’s authority before the issuance of an award or during the arbitral proceedings, and is therefore conceptually distinct from both nullity and annulment.

The study further demonstrates that a substantial part of inconsistency in Iranian judicial practice stems from the failure to distinguish defects affecting the essence and validity of the award from procedural defects affecting the arbitral process.