In modern economies, states have transitioned from direct intervention to regulatory roles, reshaping their market presence This shift is exemplified by the supervision of market participants through established competitive rules and dedicated regulatory institutions, aimed at cultivating healthy competition and preventing anti-competitive conduct. While the principal objective of competition law remains the enhancement of economic efficiency, this article contends that distributive justice constitutes a crucial dimension of market regulation. Its significance is underscored by imperatives such as safeguarding small and nascent enterprises, mitigating societal inequality, and augmenting consumer welfare. This research conducts a comparative analysis of the realization of distributive justice within the competition law frameworks of Iran and the United States. The Iranian system, despite explicit legal prohibitions against monopoly and unjust discrimination, has achieved limited success in promoting distributive justice. This shortfall is attributed to profound structural challenges, substantive weaknesses in the legal framework, and a critical lack of autonomy vested in its regulatory body. Conversely, the United States antitrust tradition explicitly prioritizes consumer welfare as its paramount goal, thereby relegating distributive justice to an indirect and secondary status. Although U.S. antitrust enforcement has indirectly influenced economic disparities, the nation continues to grapple with severe and escalating income inequality, signaling the inadequacy of its current approach in addressing distributive concerns. The core finding of this study is that neither jurisdiction has successfully established a robust and effective linkage between competition regulation and the pursuit of distributive justice. Shared impediments include the insufficient explicit codification of distributive justice within primary legislation, a deficit in practical operational mechanisms to integrate distributive objectives into judicial and executive decision-making, and the absence of meaningful independence for regulatory agencies. To bridge this gap, the study proposes concrete reforms: undertaking legislative revision to explicitly enshrine distributive justice as a goal, reinforcing operational tools for achieving distributive aims in practice, and granting greater autonomy to sectoral and cross-sectoral regulators to insulate them from external pressures.