Ernst Hammer (20 October 1884 – 2 December 1957) was a German-Austrian officer of four armies since 1 October 1903, entering as a one-year volunteer.
He was Oberleutnant of the Common Army, Hauptmann of the k.u.k.
Armee, Generalmajor of the Bundesheer (transferred to the German Army 15 March 1938), Generalleutnant of the Wehrmacht during World War II.
He was a recipient of the Knight's Cross of the Iron Cross.