Adelong is a small town in the Riverina region of New South Wales, Australia and is a part of the Tumut Shire. The Adelong district has a population of about 1400, while Adelong itself has a population of 829 people.
The town is situated about 160 kilometres west of Canberra. It is on the Snowy Mountains Highway.
The town's name is said to be derived from an Aboriginal language meaning "along the way" or "plain with a river".
It was settled about 1840 to 1850 before gold was found. The initial discovery of gold at Adelong by a Mr Williams took place in 1857, the find being located on the crest of Victoria Hill and representing the weathered capping of the Old Hill Reef. Alluvial gold, both in Adelong Creek and Golden Gully is also believed to have been discovered at about the same time, and the field quickly developed into an important producer.
Adelong Post Office opened on 1 January 1859.