Hans Georg Hermann von Plessen (26 November 1841 – 28 January 1929) was a Prussian Colonel General with the rank of Generalfeldmarschall and Canon of Brandenburg. He held the office of His Majesty's Orderly Adjutant General (German: SM diensttuender Generaladjutant) to Kaiser Wilhelm II, thus making him one of the Emperor's closest confidants. During World War I he simultaneously served as Commandant of the Imperial Grand Headquarters.