Tolštejn Castle (German: Tollenstein) is a ruin of a medieval castle in the municipal area of Jiřetín pod Jedlovou in the Ústí nad Labem Region of the Czech Republic.

It is located approximately 4 kilometres (2.5 mi) south of Varnsdorf.

The Wartenberg family owned the castle until around 1402, when it was acquired by lords of Dubá.

In 1481, the manor with the castle became a property of Schleinitz family from Saxony.

During the Thirty Years' War in 1642 it was burned down by Swedish Army and was never restored.