Ernst Eduard Samuel Fraenkel (born October 16, 1881, Berlin and died October 2, 1957, Hamburg) was a German linguist who made major contributions to the fields of Indo-European linguistics and Baltic studies.
Starting in 1899 Fraenkel studied classical philology, Sanskrit, and Indo-European linguistics with Johannes Schmidt at the Humboldt-Universität zu Berlin. In 1905 he defended his dissertation about ancient Greek denominal verbs. From 1906 to 1908 he studied with August Leskien, an expert on the Baltic languages, in Leipzig. In 1909 he became a Privatdozent at the Christian-Albrechts-Universität zu Kiel. In 1916 he became an außerordentlicher Professor and in 1920 ordentlicher Professor. Although his parents had converted to Protestants, starting in 1936 his Jewish background prompted his dismissal from the university on the basis of the Nuremberg laws of Nazi Germany, and he was also not allowed to publish scholarly works in Germany. From 1945 to 1954 he led the Seminar für vergleichende Sprachwissenschaft in Hamburg.