Domingo Báñez (29 February 1528 in Valladolid – 22 October 1604 in Medina del Campo) was a Spanish Dominican and Scholastic theologian. The qualifying Mondragonensis sometimes attached to his name seems to refer to the birthplace of his father, Juan Báñez, at Mondragón in Guipúzcoa.
Báñez was born at Medina del Campo, in the province of Valladolid.
"At fifteen he began to study philosophy at the University of Salamanca. Three years later he took the Dominican habit at the Convent of St. Stephen, Salamanca, and made his profession 3 May 1547. During a year's review of the liberal arts and later, he had the afterwards distinguished Bartolomé Medina as a fellow student. Under such professors as Melchior Cano (1548–51), Diego de Chaves (1551), and Pedro Sotomayor (1550–51) he studied theology, laying the foundations of the erudition and acquiring the acumen which later made him eminent as a theologian and an exponent and defender of Thomistic doctrine. Báñez next began teaching, and under Domingo Soto, as prior and regent, he held various professorships for ten years. He was made master of students, explaining the Summa to the younger brethren for five years, and incidentally taking the place, with marked success, of professors who were sick, or who for other reasons were absent from their chairs at the university. In the customary, sometimes competitive, examinations before advancement he is said easily to have carried off all honours. Báñez taught at the Dominican University of Avila from 1561 to 1566. About 1567 he was assigned to a chair of theology at Alcalá, the ancient Complutum. It appears that he was at Salamanca again in 1572 and 1573, but during the four scholastic years 1573-77 he was regent of St. Gregory's Dominican College al Valladolid, a house of higher studies where the best students of the Castilian province were prepared for a scholastic career. Elected Prior of Toro, he went instead to Salamanca to compete for the chair of Durandus, left vacant by Medina's promotion to the chief professorship. He occupied this position from 1577 to 1580. After Medina's death (30 December 1580) he appeared again as competitor for the first chair of the university. The outcome was an academic triumph for Báñez and he was duly installed in his new position amid the acclamations of professors and students. There he laboured for nearly twenty years. His name acquired extraordinary authority, and the leading schools of orthodox Spain referred to him as the proeclarissimum jubar-- "the brightest light"—of their country."