Rathenau is a German locational surname, named after the obsolete spelling for the town of Rathenow in Brandenburg. The name may refer to:
Emil Rathenau (1838–1915), German industrialist Gerhart Rathenau (1911–1989), Dutch scientist Walther Rathenau (1867–1922), German industrialist and politician
Other uses Walther Rathenau Institut, a thinktank in Berlin
See also Ratner (disambiguation)