Religion in Cyprus is dominated by the Eastern Orthodox branch of Christianity, whose adherents make up 73% of the total population of the entire island. Most Greek Cypriots are members of the autocephalous Greek Orthodox 'Church of Cyprus'. Most Turkish Cypriots are officially Sunni Muslims. There are also Baháʼí, Catholic, Jewish, Protestant (including Anglican), Armenian Apostolic, Sikh and non-religious communities in Cyprus.

Religious statistics for Cyprus vary depending on whether they refer to the government-controlled area of the Republic of Cyprus or the island as a whole, including the Turkish Cypriot-administered north. The Republic of Cyprus census records religion in the government-controlled area, while international estimates such as those from the Pew Research Center attempt to describe the religious composition of the entire island.

The 2021 census recorded Eastern Orthodox Christianity as the largest religious affiliation in the government-controlled area, accounting for 74.5% of all inhabitants. The proportion of respondents whose religion was not stated increased to 17.3%, compared with 1.1% in 2011. Several minority religions represented a larger share of all inhabitants than of Cypriot citizens, reflecting the effect of non-citizen residents on the religious composition recorded by the census.

Cyprus is a place where many New Testament biblical stories took place, mainly told in the Book of Acts, a few years after the Crucifixion of Jesus.

According to tradition, the first bishops in Cyprus were the apostles Lazarus (see Church of Saint Lazarus, Larnaca) and Barnabas, the latter of whom is identified by the Book of Acts as a Cypriot Jew. The same book names Cyprus as a destination for many early Christians fleeing persecution.^{[better source needed]}

The largest and most important church in Cyprus, the Church of Cyprus, is an autocephalous Greek Orthodox Church within the Orthodox tradition using the Greek liturgy. It is one of the oldest Eastern Orthodox autocephalous churches, having achieved independence from the Patriarchate of Antioch in 431 AD.

The Church of Cyprus recognises the seniority and prestige of the ecumenical patriarch of Constantinople, while retaining complete administrative autonomy under its own archbishop. Seven sacraments are recognised: baptism in infancy, followed by confirmation with consecrated oil, penance, the Eucharist, matrimony, ordination, and unction in times of sickness or when near death.

Many examples of classical Christian architecture are located in Cyprus, along with tombs said to belong to Lazarus and Barnabas.