This article highlights the role of Majelis Ulama Indonesia in making anti-pluralism discourse and practice which are evident in its fatwa on belief . It begins with the explanation of MUI which in the first three decades of its establishment was a fatwa body that supported pluralism, but since the downfall of the authoritarian Suharto regime in 1998, has changed its position from supporter to detractor of pluralism. This article argues that the institutionalization of anti- pluralism discourse through the MUI (...) fatwa creates complexity especially because Indonesia contains the idea of pluralism in its constitution. The situation becomes more complex when the state and also Muslim organizations strengthen the position of MUI in monopolizing fatwa-making on ‘aqīda issues. The monopolization of fatwa on Islamic belief issues creates such a negative impact for religious freedom in Indonesia due to its fundamental characteristics that allow only a single judgment for the Muslim communities in understanding and interpreting their Islamic belief. Finally this article concludes the importance of Indonesia for protecting pluralism for maintaining the diversity of cultures and religions in this country. (shrink)