Look up Orthodox Church in Wiktionary, the free dictionary.

Orthodox Church may refer to:

• Eastern Orthodox Church, the second-largest Christian church
• Oriental Orthodox Churches, a branch of Eastern Christianity
• 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 380 CE
• True Orthodox church, a movement within Eastern Orthodox Christianity