Originally named Dalldorf it was first mentioned in 1332. In 1869 the city of Berlin had acquired land in the Dalldorf in order to built the Städtische Irrenanstalt zu Dalldorf (City-owned Madhouse at Dalldorf), today's Karl-Bonhoeffer-Nervenklinik (Karl Bonhoeffer mental home), between 1877 and 1879. In the following years Dalldorf became the synonym for 'madhouse' in Berlin parlance. Therefore in 1903 Dalldorf applied at the Niederbarnim district commissioner for a new toponym, Wittenau after its late mayor Peter Witte, granted by the Prussian government with effect of 23 August 1905. In 1920 Wittenau merged into Berlin by the Greater Berlin Act.
Wittenau's former neighbourhood Märkisches Viertel was elevated to locality status in 1999. Until 24 April 2012 Borsigwalde, now also a locality of its own, was part of Wittenau.