Otto VI, Count of Weimar-Orlamünde

Otto VI (1297–1340) was the last Ascanian count of Weimar-Orlamünde at the Plassenburg, son of Count Otto IV and Adelheid of Kevernburg. He married Kunigunde of Leuchtenberg, but the marriage remained childless; legend nevertheless made her the model of the Hohenzollern White Lady who killed her two children.

In 1337 Otto made an inheritance agreement with Burgrave John of Nuremberg. By his death in 1340, he had borrowed four thousand pounds from John against the Plassenburg, which passed to the Hohenzollern burgraves.