Heinrich Friedrich Wilhelm Gesenius (3 February 1786 – 23 October 1842) was a German orientalist, Lutheran, and Biblical critic.
He was born at Nordhausen. In 1803 he became a student of philosophy and theology at the University of Helmstedt, where Heinrich Henke was his most influential teacher; but the latter part of his university course was taken at Göttingen, where Johann Gottfried Eichhorn and Thomas Christian Tychsen were then at the height of their popularity. In 1806, shortly after graduation, he became Repetent and Privatdozent at Göttingen; and, as he was later proud to say, had August Neander for his first pupil in Hebrew language. In 1810 he became professor extraordinarius in theology, and in 1811 ordinarius, at the University of Halle, where, in spite of many offers of high preferment elsewhere, he spent the rest of his life.
He taught with great regularity for over thirty years. The only interruptions occurred in 1813–1814, occasioned by the German War of Liberation (War of the Sixth Coalition), during which the university was closed, and those occasioned by two prolonged literary tours, first in 1820 to Paris, London and Oxford with his colleague Johann Karl Thilo (1794–1853) for the examination of rare oriental manuscripts, and in 1835 to England and the Netherlands in connection with his Phoenician studies. He became the most popular teacher of Hebrew and of Old Testament introduction and exegesis in Germany; during his later years his lectures were attended by nearly five hundred students. Among his pupils the most eminent were Peter von Bohlen, C. P. W. Gramberg, A. G. Hoffmann, Hermann Hupfeld, Emil Rödiger, J. F. Tuch, Johann Karl Wilhelm Vatke and Theodor Benfey.