Eastern Orthodoxy in Montenegro refers to adherents, religious communities, institutions and organizations of Eastern Orthodox Christianity in Montenegro. It is the largest Christian denomination in the country. According to the latest census of 2011, 446,858 citizens of Montenegro (72.07%) registered as Eastern Orthodox Christians. The majority of Eastern Orthodox people in Montenegro are adherents of the Serbian Orthodox Church. A minor percentage supports the noncanonical and unrecognized Montenegrin Orthodox Church, which has the status of a religious non-governmental organization (NGO) since its founding in 1993.

The Montenegrin Orthodox Church is a canonically unrecognized Eastern Orthodox Church. It was formed in 1993 and registered as a non-governmental organization. Antonije Abramović was appointed as its first metropolitan. It claims succession to an older and autocephalous Montenegrin Church, which operated until the unification of the Kingdom of Serbia and Kingdom of Montenegro, later to join the Kingdom of Serbs, Croats and Slovenes in 1918.