Louis Veuillot (October 11, 1813 - March 7, 1883) was a French journalist and man of letters.

He was born of humble parents at Boynes (Loiret). When he was five, his parents moved to Paris. With little education, he entered a lawyer's office, and was sent in 1830 to serve on a Rouen paper, and afterwards to Périgueux. He returned to Paris in 1837, and a year later visited Rome during Holy Week. There he embraced extravagant ultramontane sentiments, and became an ardent champion of Catholicism. The results of his conversion appeared in Pélerinages en Suisse (1839), Rome et Lorette (1841) and other works.

In 1843 he joined the staff of the Univers religieux. His methods of journalism had already provoked more than one duel, and for his polemics against the University of Paris in the Univers he was imprisoned for a short time. In 1848 he became editor of the paper, which was suppressed in 1860, but revived in 1867, when Veuillot continued his ultramontane propaganda, bringing about a second suppression of his journal in 1874. Veuillot then occupied himself in writing violent pamphlets against the moderate Catholics, the Second French Empire and the Italian government. His services to the papal see were fully recognized by Pope Pius IX, on whom he wrote (1878) a monograph.

Some of his scattered papers were collected in Mélanges religieux, historiques et littéraires (12 vols., 1857-1875), and his Correspondance (6 vols., 1883-85) has great political interest. His younger brother, Eugène Veuillot , published (1901-1904) a comprehensive and valuable life, Louis Veuillot.