St. Gregory's Abbey, Benedictine monastery in Shawnee, United States.

St. Gregory's Abbey is a Benedictine monastery in Shawnee, Oklahoma, belonging to the American-Cassinese Congregation. Its grounds include Benedictine Hall, the main building of the former St. Gregory's University campus, which closed in 2017 and is now owned by the abbey. The abbey and former college grounds are listed on the National Register of Historic Places.

Benedictine monks from France arrived in Louisiana in 1873 and moved to Indian Territory in October 1875 at the suggestion of Archbishop Napoléon-Joseph Perché of New Orleans. In 1876 they founded Sacred Heart Abbey at present-day Konawa, led by Rev. Dom Isidore Robot, O.S.B., whom the Holy See had appointed Prefect Apostolic of the Indian Territory. A fire destroyed much of the abbey in 1901, and at the city's invitation the monks rebuilt in Shawnee, establishing St. Gregory's College and High School.

The community follows Benedictine principles that weave together prayer, craftsmanship, and daily work in a structured rhythm. Visitors can observe this way of life through the regular prayer services that shape each day.

The monastery welcomes visitors during prayer times, which occur throughout the day and offer insight into monastic life. It is wise to plan ahead and check access times, as entry may be limited.

The former campus of St. Gregory's University, including Benedictine Hall, passed briefly to Oklahoma Baptist University's Green Campus before the abbey reacquired it. The abbey and former college grounds are listed on the National Register of Historic Places in Pottawatomie County.