Otto VI, Margrave of Brandenburg-Salzwedel

Otto VI, Margrave of Brandenburg-Salzwedel, nicknamed Otto the Short (c. 1255 – 1303 in Lehnin) was a member of the House of Ascania and co-ruler of Brandenburg. He was a son of Margrave Otto III and his wife, Beatrice of Bohemia.

In 1267, his father died and Otto succeeded as margrave, jointly with his brothers and cousins.

In 1279, Otto married Hedwig, the daughter of King Rudolph I of Germany. This marriage remained childless.

In 1286, he abdicated and became a Knight Templar. Later, he became a Cistercian monk. He died in 1303, around the age of 48.