奥思定会（Augustinians，或思定会），是遵行《圣奥斯定会规》生活的男女修会的总称。

奥思定会有2个主要分支：

The Order of St. Augustine (Latin:Ordo sancti Augustini, abbreviated as O.S.A.)—historically Ordo eremitarum sancti Augustini", O.E.S.A., the Order of Hermits of St. Augustine), generally called Augustinians (but not to be confused with the Augustinian Canons Regular) is a Catholic Religious Order, which, although more ancient, was formally created in the thirteenth century and combined several previous Augustinian eremetical Orders into one. In its establishment in its current form, it was shaped as a mendicant Order, one of the four great Orders which follow that way of life. The Order has done much to extend the influence of the Church, to propagate the Roman Catholic Faith and to advance learning. The Order has, in particular, spread internationally the veneration of the Virgin Mary under the title of Our Lady of Good Counsel (Mater boni consilii).