Francis Lambert (c. 1486 – April 8, 1530) was a Protestant reformer, the son of a papal official at Avignon, where he was born between 1485 and 1487.
At the age of 15 he entered the Franciscan monastery at Avignon, and after 1517 he was an itinerant preacher, travelling through France, Italy and Switzerland. His study of the Scriptures shook his faith in Roman Catholic theology, and by 1522 he had abandoned his order, and became known to the leaders of the Reformation in Switzerland and Germany. He did not, however, identify himself either with Zwinglianism or Lutheranism; he disputed with Zwingli at Zürich in 1522, and then made his way to Eisenach and Wittenberg, where he married in 1523.
He arrived in Strasbourg in 1524, being anxious to spread the doctrines of the Reformation among the French-speaking population of the city. By the Germans he was distrusted, and in 1526 his activities were prohibited by the city. He was, however, befriended by Jacob Sturm, who recommended him to the Landgraf Philip of Hesse, the most liberal of the German reforming princes. With Philip's encouragement he drafted that scheme of ecclesiastical reform for which he is famous.