Hardenberg and von Hardenberg are German surnames. Notable people with these surnames include:
Albert Hardenberg (c. 1510–1574), Reformed theologian
Anne Hardenberg (died 1588), Danish noblewoman.
Astrid Gräfin von Hardenberg (1925–2015), daughter of Carl-Hans Graf von Hardenberg
Carl-Hans Graf von Hardenberg (1891–1958), German politician
Georg Philipp Friedrich Freiherr von Hardenberg (1772–1801), German poet known as Novalis
Henriette Hardenberg (1894–1993), German Expressionist poet
Karl August von Hardenberg (1750–1822), Prussian statesman
Mette Hardenberg (1569–1629), Danish noble and landowner
Tita von Hardenberg (born 1968), stage name of German television journalist Katharina Isabel Gräfin von Hardenberg
