Ernst Steindorff (June 15, 1839 – April 9, 1895) was a German historian who was a native of Flensburg.
He studied history at the Universities of Kiel, Göttingen and Berlin. In 1873 he was an associate professor of history at Göttingen, where in 1883 he became a full professor.
Steindorff is remembered as author of the two-volume Jahrbücher des Deutschen Reichs unter Heinrich III (Annals of the German Empire under Henry III) (1874-81). He also published the sixth edition of the Dahlmann-Waitz Quellenkunde der Deutschen Geschichte.