Otto IV of Bergau (German: Otto dem Jüngeren von Bergow; 1399 – 1452), also known as Otto the Younger of Bergau, was a Bohemian nobleman and anti-Hussite leader.

He inherited parts of his father's estate including Trosky Castle and Chlumec nad Cidlinou.

[2] He is said to have hidden the treasure in Trosky Castle, supposedly in an underground cellar blocked by a huge boulder.

[3] In 1424, Chlumec nad Cidlinou was captured by the Prague Hussites under the leadership of Sigismund Korybut and Jan Hvězda of Vícemilice [cs].

Otto and his son, John, reclaimed Chlumec shortly thereafter.