Ensuring the rule of law necessitates the establishment of efficient regulatory oversight mechanisms; however, the multiplicity of oversight bodies in Iran and the overlap of political and judicial competencies—particularly regarding the authority of the Speaker of the Parliament in relation to the Court of Administrative Justice—have posed significant challenges to the comprehensiveness of judicial review. Accordingly, the central question of this research is: what are the structural and functional distinctions between the regulatory oversight mechanisms in the selected countries (the United States, France, and Japan) and the Iranian system, and what insights do they offer for addressing Iran’s regulatory gaps? Utilizing a descriptive-analytical method and legal document analysis, this study provides a systemic inquiry into these mechanisms. The findings indicate that the U.S. system relies on comprehensive judicial review, congressional oversight, and ex-ante review by the Office of Information and Regulatory Affairs. France implements a dual model of ex-ante (consultative) and ex-post oversight through the Council of State, while Japan employs a combination of ex-ante review by the Cabinet Legislation Bureau and ex-post judicial review. Comparatively, while the Iranian system utilizes a multi-layered model, it suffers from the absence of organized ex-ante oversight. Furthermore, the Speaker of the Parliament’s unique authority over government approvals serves as a mechanism that can lead to the curtailment of the Court of Administrative Justice’s jurisdiction as the supreme judicial authority. The research concludes that aligning Iran’s current model with global rule-of-law standards requires strengthening the independence of judicial review and re-evaluating political oversight mechanisms.