In recent years, competition over the norms and rules governing digital space has transformed regional organizations into arenas for shaping divergent approaches to information security and cyber governance. The present study examines the normative and institutional mechanisms through which the Shanghai Cooperation Organization (SCO) facilitates the convergence of Iranian and Russian cyber diplomacy in addressing information threats and disinformation. Employing a qualitative document analysis method and drawing upon international institutionalism and the literature on norm diffusion, the study scrutinizes official SCO documents, relevant policy documents, and bilateral evidence from Iran and Russia. The findings indicate that the organization's role is primarily observable at two levels: first, the reproduction of norms such as information security, cyber sovereignty, and the right of states to regulate their national information space; and second, the provision of regular consultative and coordinative mechanisms in the domain of information security. Bilateral evidence from Iran and Russia further indicates a relative convergence in certain security perceptions and principles of digital space governance, although this evidence should not be equated with the formal mechanisms of the SCO. Accordingly, the SCO may be assessed less as a direct driver of operational anti-disinformation cooperation and more as a normative and institutional platform facilitating the limited convergence of the two states in the realms of information security and cyber governance.