Thomas Langdon Grace OP (November 14, 1814 – February 22, 1897) was an American prelate who served as the second Roman Catholic Bishop of Saint Paul, Minnesota.

Born in Charleston, South Carolina, Grace entered the seminary at Cincinnati in 1829, and, the following year, was admitted to the Dominican Order at the Priory of St. Rose in Kentucky, where he made his religious profession on 12 June 1831.

[2] Pope Pius IX appointed Grace to succeed Joseph Crétin as the Bishop of the Diocese of Saint Paul in Minnesota on January 21, 1859, for which he was consecrated on July 24, 1859.

On September 24, 1889, in recognition of his service as bishop, he was appointed to the titular see of Siuna, with the personal title of archbishop.

[5][2] Upon his death in Merriam Park on February 22, 1897, Grace's funeral was held at the cathedral and he was buried in Calvary Cemetery in Saint Paul.