August Hahn (March 27, 1792 - May 13, 1863), German Protestant theologian, was born at Grossosterhausen near Eisleben, and studied theology at the university of Leipzig.

In 1819 he was nominated professor extraordinarius of theology and pastor of Altstadt in Königsberg, and in 1820 received a superintendency in that city. In 1822 he became professor ordinarius. In 1826 he removed as professor of theology to Leipzig, where, hitherto distinguished only as editor of Bardesanes , Marcion (Marcions Evangelium in seiner ursprunglichen Gestalt, 1823), and Ephraem Syrus, and the joint editor of a Syrische Chrestomathie (1824), he came into great prominence as the author of a treatise, De rationalismi qui dicitur vera indole et qua cum naturalismo cant ineatur ratione (1827), and also of an Offene Erklarung an die Evangelische Kirche zunachst in Sachsen u. Preussen (1827), in which, as a member of the school of EW Hengstenberg, he endeavoured to convince the rationalists that it was their duty voluntarily and at once to withdraw from the national church.

In 1833 Hahn's pamphlet against KG Bretschneider (Uber die Lage des Christenthums in unserer Zeit, 1832) having attracted the notice of Friedrich Wilhelm III, he was called to Breslau as theological professor and consistorial councillor, and in 1843 became general superintendent of the province of Silesia. He died at Breslau on the 13th of May 1863. His son, Heinrich was also a theologian.

Though uncompromising in his supra-naturalism, he did not altogether satisfy the men of his own school by his own doctrinal system. The first edition of his Lehrbuch des christlichen Glaubens (1828) was freely characterized as lacking in consistency and as detracting from the strength of the old positions in many important points. Many of these defects, however, he is considered to have remedied in his second edition (1857).

Among his other works are his edition of the Hebrew Bible (1833), his Bibliothek der Symbole and Glaubensregeln der apostolisch-katholischen Kirche (1842; 2nd ed. 1877) and Predigten (1852).