Several Christian Churches or church bodies are named or commonly referred to as "Orthodox Church". The term designates more commonly first the Eastern Orthodox Church, and second the Oriental Orthodox Churches.
Eastern Orthodox Church
Mainstream autocephalous Churches
- Orthodox Church of Constantinople
- Greek Orthodox Church of Alexandria
- Greek Orthodox Church of Antioch
- Greek Orthodox Church of Jerusalem
- Russian Orthodox Church
- Georgian Orthodox Church
- Serbian Orthodox Church
- Romanian Orthodox Church
- Bulgarian Orthodox Church
- Orthodox Church of Cyprus
- Orthodox Church of Greece
- Orthodox Church of Albania
- Polish Orthodox Church
- Orthodox Church of the Czech Lands and Slovakia
- Orthodox Church in America
- Orthodox Church of Ukraine
Major mainstream autonomous Churches
- Orthodox Church of Sinai (under the Greek Orthodox Church of Jerusalem)
- Orthodox Church of Finland (under the Orthodox Church of Constantinople)
- Orthodox Church of Japan (under the Russian Orthodox Church)
- Orthodox Church of Ukraine (Moscow Patriarchate) (under the Russian Orthodox Church)
- Russian Orthodox Church Outside of Russia (under the Russian Orthodox Church)
Other Eastern Orthodox Churches
- Eastern Orthodox Church organization § Unrecognized churches
- True Orthodoxy, a movement that separated from the mainstream Eastern Orthodox Church in the 1920s over issues of ecumenism and calendar reform
- Holy Synod of Milan
- Autonomous Orthodox Metropolia of North and South America and the British Isles
- Autonomous Orthodox Metropolis of Ecuador and Latin America
- True Orthodox Metropolis of Germany and Europe
- Old Calendar Bulgarian Orthodox Church
- Old Calendarist Romanian Orthodox Church
- Russian Orthodox Autonomous Church
- Russian True Orthodox Church (Lazar Zhurbenko)
- Serbian True Orthodox Church
- Greek Old Calendarists
- True Orthodoxy, a movement that separated from the mainstream Eastern Orthodox Church in the 1920s over issues of ecumenism and calendar reform
By country
Oriental Orthodox Churches
- Armenian Apostolic Church
- Holy See of Cilicia
- Coptic Orthodox Church of Alexandria
- Syriac Orthodox Church of Antioch
- Assyrian Church of the East
- Ancient Church of the East
- Ethiopian Orthodox Tewahedo Church
- Eritrean Orthodox Tewahedo Church
- Indian Orthodox Church
By country
Protestant Churches
Other
- Proto-orthodox Christianity, a term coined by New Testament scholar Bart D. Ehrman to describe the Early Christian movement which was the precursor of Christian orthodoxy
- Western Rite Orthodoxy
- Ancient British Church
- Communion of Western Orthodox Churches, a communion of Christian churches of Eastern and Oriental Orthodox tradition distinguished by its adherence to the liturgical and spiritual customs of western Christianity
- British Orthodox Church