Look up Orthodox Church in Wiktionary, the free dictionary.
The Orthodox Church and Orthodox Christianity most often refer to one of two Eastern Christian churches:
- Eastern Orthodox Church, the second-largest Christian church in the world
- Oriental Orthodox Churches, a branch of Eastern Christianity
Orthodox Church may also refer to:
- Early Church, the Christian religion prior to the First Council of Nicaea
- Christian orthodoxy, the doctrines subscribed to by the early church
- Orthodox Anglican Communion, a communion of Anglican churches
- African Orthodox Church, a predominantly African-American Christian denomination
- Evangelical Orthodox Church, an Eastern Protestant Christian denomination
- Orthodox Presbyterian Church, a confessional Presbyterian denomination located primarily in the United States
- Orthodox Presbyterian Church of New Zealand, a denomination formed in the 1960s led by George Mackenzie
- State church of the Roman Empire, Roman Empire's state religion after AD 380
