The Patriarch of Moscow and all Rus' (Russian: Патриарх Московский и всея Руси, romanized: Patriarkh Moskovskiy i vseya Rusi), also known as the Patriarch of Moscow and all Russia, is the title of the primate of the Russian Orthodox Church (ROC). It is often preceded by the honorific "His Holiness". As the ordinary of the diocese of Moscow, the office holder's direct canonical remit extends only to Moscow; however, as the patriarch, the office holder has a number of church-wide administrative powers as laid down by the charter of the ROC.

The patriarchate was established in 1589 when the status of the Russian metropolitan was elevated, with Job becoming the first patriarch. The patriarchate was abolished in 1721 by Peter the Great and replaced with the Most Holy Synod as the supreme governing body of the ROC, before being restored on 10 November [O.S. 28 October] 1917, by decision of the All-Russian Local Council. The current patriarch is Kirill, who acceded to the position in 2009.

Different variations of the title of the patriarch have been used, including Patriarch of Moscow and all Russia, Patriarch of Moscow and all Great and Little and White Russia, among others. The current version of the title was first used in 1589 and restored beginning in 1917 until suspended by Soviet authorities in 1925, and since being reinstated with the election of Metropolitan Sergius as the patriarch in 1943.

The history of the Russian Orthodox Church (ROC) begins with the Christianization of Kievan Rus' in 988 during the reign of Vladimir the Great. Under Vladimir, the metropolis of Kiev was established and it remained under the jurisdiction of the patriarch of Constantinople until 1589. After Kiev lost its significance, the seat of the metropolitan was moved to Vladimir in 1299. In 1325, it was moved to Moscow.

The ROC declared autocephaly in 1448, shortly before the fall of Constantinople, owing to its protest over the Council of Florence. The Russian Church came to function independently as a council of Russian bishops elected their own metropolitan without reference to Constantinople.

After Constantinople fell in 1453, Moscow became the only independent Orthodox power and its leaders soon began to advance the claim that Moscow was the successor to the Byzantine Empire, calling it the "third Rome". The fall of Constantinople, viewed by the Russians as divine punishment, confirmed the nascent independence of the Russian Church. The political and territorial consolidation of Russia was reflected by the unification and standardization of Orthodoxy.

In 1589, Metropolitan Job was consecrated as the first Russian patriarch with the blessing of Jeremias II of Constantinople. As a result, the patriarchate was granted equal status to those of Constantinople, Antioch, Jerusalem and Alexandria. In the decree establishing the patriarchate, the whole Russian tsardom is called a "third Rome".

In 1590, a council held in Constantinople confirmed the new status of Moscow, and three years later, the four other Orthodox patriarchs ratified this at another council with the support of 42 bishops. Moscow differed in that it was the only independent Orthodox power and this led to the culmination of the idea that Moscow was the "third Rome". The Russian Church was accorded the fifth place in the diptych of the Eastern Orthodox Church.