Lydenburg is a town in Thaba Chweu Local Municipality, Mpumalanga, South Africa. Alternatively known as Mashishing, Lydenburg is situated on the Sterkspruit/Dorps River tributary of the Lepelle River at the base of the Long Tom Pass. The name is derived from the Dutch Lijdenburg, or "Town of Suffering".
Lydenburg is an important centre for farming, and is also home to one of Mpumalanga's best museums detailing the mysterious history of the famed Lydenburg Heads, which are unique pottery masks made by a vanished people thousands of years ago, and believed to have served a ritual or religious purpose.