St. Thérèse of Lisieux, also called St. Teresa of the Child Jesus or the Little Flower, original name Marie-Françoise-Thérèse Martin, (born January 2, 1873, Alençon, France—died September 30, 1897, Lisieux; canonized May 17, 1925; feast day October 1), Carmelite nun whose service to her Roman Catholic order, although outwardly unremarkable, was later recognized for its exemplary spiritual accomplishments. She was named a doctor of the church by Pope John Paul II in 1997.

Thérèse was the youngest of nine children, five of whom survived childhood. After her mother died of breast cancer in 1877, Thérèse moved with her family to Lisieux. In the deeply religious atmosphere of her home, her piety developed early and intensively. All four of her elder sisters became nuns, and at the age of 15 she entered the Carmelite convent at Lisieux, having been refused admission a year earlier. Although she suffered from depression, scruples—a causeless feeling of guilt—and, at the end, religious doubts, she kept the rule to perfection and maintained a smiling, pleasant, and unselfish manner. Before her death from tuberculosis, she acknowledged that, because of her difficult nature, not one day had ever passed without a struggle. Her burial site at Lisieux became a place of pilgrimage, and a basilica bearing her name was built there (1929–54).