Altenau (disambiguation)

Altenau is a town in Lower Saxony.

Altenau may also refer to:
 * Altenau (Oker), a tributary of the Oker in eastern Lower Saxony
 * Altenau (Alme), a tributary of the Alme in eastern North Rhine-Westphalia
 * Altenau, a part of Mühlberg, Brandenburg, Germany

People with the surname

 * Cornelis Altenau (died 1558), Danish-German builder