Christian liturgy is a pattern for worship used (whether recommended or prescribed) by a Christian congregation or denomination on a regular basis. The term liturgy comes from Greek and means "public work". Within Christianity, liturgies descending from the same region, denomination, or culture are described as ritual families.

When Christians meet for worship, they perform a liturgy (work), offering service to God together. The majority of Christian denominations hold their principal church service on Sunday, the first day of the week, which is known as the Lord's Day. In some Christian denominations, liturgies are held daily, with these including those in which the canonical hours are prayed, as well as the offering of the Eucharistic liturgies such as Mass, among other forms of worship. In addition to this, many Christians attend services of worship on holy days such as Christmas, Ash Wednesday, Good Friday, Ascension Thursday, among others depending on the Christian denomination.

Liturgies are generally presided over by clergy, wherever possible, in some Christian traditions, but lay leaders of worship preside over services in many cases.

The holding of church services pertains to the observance of the Lord's Day in Christianity. The Bible has a precedent for a pattern of morning and evening worship that has given rise to Sunday morning and Sunday evening services of worship held in the churches of many Christian denominations today, a "structure to help families sanctify the Lord's Day." In Numbers 28:1–10 and Exodus 29:38–39, "God commanded the daily offerings in the tabernacle to be made once in the morning and then again at twilight". In Psalm 92, which is a prayer concerning the observance of the Sabbath, the prophet David writes "It is good to give thanks to the Lord, to sing praises to your name, O Most High; to declare your steadfast love in the morning, and your faithfulness by night" (cf. Psalm 134:1). Church father Eusebius of Caesarea thus declared: "For it is surely no small sign of God's power that throughout the whole world in the churches of God at the morning rising of the sun and at the evening hours, hymns, praises, and truly divine delights are offered to God. God's delights are indeed the hymns sent up everywhere on earth in his Church at the times of morning and evening."

Communion liturgies are those in which the Eucharist is celebrated.

In the Roman Catholic Church, the sacred liturgy in which the Eucharist is celebrated is generally called the Mass. In Latin, the corresponding word is Missa, taken from the dismissal at the end of the liturgy - Ite, Missa est, literally "Go, it is the dismissal", translated idiomatically in the current English Roman Missal as "Go forth, the Mass is ended."^{[citation needed]}

The Eastern Orthodox Church (Byzantine Rite) uses the term "Divine Liturgy" to denote the Eucharistic service, and some Oriental Orthodox churches also use that term, along with the Eastern Lutheran Churches and the Eastern Catholic Churches.

The descendant churches of the Church of the East and various other Syriac Churches call their Liturgy the Holy Qurbana, meaning "Holy Offering".