Johannes Valentinus Andreae a.k.a. Johannes Valentinus Andreä or Johann Valentin Andreae, was a German theologian, who claimed to be the author of the Chymische Hochzeit Christiani Rosencreutz anno 1459 (1616, Strasbourg, the Chymical Wedding of Christian Rosenkreutz), one of the three founding works of Rosicrucianism.

He studied theology and natural sciences in Tübingen,obtaining a degree in 1614. He became a priest in Calw. Here he reformed the school and social institutions, and established institutions for charity and other aids. To this end, he initiated the Christliche Gottliebende Gesellschaft ("Christian God-loving Society"). In 1628 he planned a "Unio Christiana".
In 1639, he became preacher at the court and councillor of the consistory (Konsistorialrat) in Stuttgart, where he advocated a fundamental church reform. He became also a spiritual adviser to a royal princess of Württemberg. In 1650, he assumed direction of the monasterial school Bebenhausen; in 1654, he became abbot of the evangelical monasterial school of Adelberg.

His role in the origin of the Rosicrucian legend is controversial. In his autobiography he indicated the Chymische Hochzeit as one of his works—as a "ludibrium", possibly meaning "lampoon". In his later works, alchemy is the object of ridicule and is placed with music, art, theatre and astrology in the category of less serious sciences.