The Church Fathers or Fathers of the Church are the early and influential theologians and writers in the Christian church, particularly those of the first five centuries CE. Those who wrote in Latin are called the Latin (Church) Fathers, and those who wrote in Greek the Greek (Church) Fathers.

Famous Latin Fathers include Saint Augustine of Hippo, the Montanist Tertullian, and Saint Jerome, the translator of the Vulgate; famous Greek Fathers include the heterodox Origen, Saint Irenaeus, Saint Clement of Alexandria, and Saint John Chrysostom.

The Desert Fathers were monastics living in the Egyptian desert; although they did not write as much, their influence was also great. Among them are Saint Anthony and Saint Pachomius.

A small number of other Fathers wrote in other languages: Saint Ephraem, for example, wrote in Syriac, but his works were widely translated into Latin and Greek.

Many of their works have been translated into English and made available to read online or download and print, at the Christian Classics Ethereal Library.