The Rule of Saint Augustine, written in about the year 400, is a brief document divided into eight chapters and serves as an outline for religious life lived in community. It is the oldest monastic rule in the Western Church.

The rule, developed by Augustine of Hippo (354–430), governs chastity, poverty, obedience, detachment from the world, the apportionment of labour, the inferiors, fraternal charity, prayer in common, fasting and abstinence proportionate to the strength of the individual, care of the sick, silence and reading during meals. It came into use on a wide scale from the twelfth century onwards and continues to be employed today by many orders, including the Dominicans, Servites, Mercederians, Norbertines, and Augustinians.

In 388, Augustine returned from Milan to his home in Thagaste. He then sold his patrimony and gave the money to the poor. The only thing he kept was the estate, which he converted into a monastic foundation for himself and a group of friends with whom he shared a life of prayer. Later as bishop he invited his priests to share a community life with him.

Augustine followed the monastic or religious life as it was known to his contemporaries, drafting rules for the monks and nuns of Roman Africa. Like St. Basil, Augustine's view diverged from that of the earlier eremitical approach of strict physical austerities. In The Ways of the Catholic Church, Augustine observed contemporary criticisms of the methods of the Eastern hermits in the Egyptian desert. It was said that their extreme isolation and excessive asceticism "were no longer productive" for the church or society. In response to this, "Augustine promoted poverty of spirit and continence of the heart while living in the milieu of a town such as Hippo."

In Hippo, the members of his monastic house lived in community while yet keeping to their pastoral obligations. For Augustine, 'the love of neighbour was simply another expression of the love of God." He saw the call to service in the church a necessitas (necessity) to be heeded, even if it compromised a personal desire for contemplation and study. One of the elements of communal living was simplicity of lifestyle. Regarding the use of property or possessions, Augustine did not make a virtue of poverty, but of sharing. Augustine wrote frequently on prayer, but prescribed no specific method, system, or posture; although he highly endorsed the psalms.

Several of his friends and disciples elevated to the episcopacy imitated his example, among them Alypius at Tagaste, Possidius at Calama, Profuturus and Fortunatus at Cirta, Evodius at Uzalis, and Boniface at Carthage.

The title, Rule of Saint Augustine, has been applied to each of the following documents:

The last is a treatise on eremitical life by Saint Ælred, Abbot of Rievaulx, England, who died in 1166. The two preceding rules are of unknown authorship. Letter 211 and Sermons 355 and 356 were written by Augustine.