Ustyuzhna is a town and the administrative center of Ustyuzhensky District in Vologda Oblast, Russia, located on the Mologa River, west of Vologda, the administrative center of the oblast. Population:

Considered to have been founded in the 11th century, it was first mentioned, as Zhelezny Ustyug , in 1252, and in the following centuries was called variously Ustyuzhna Zheleznopolskaya, Ustizhna, Ustizhnya, Ustyuzhnya, and Yustyzhnya. In the 16th–18th centuries it was known mostly as Ustyuzhna-Zheleznaya or Ustyuzhna-Zheleznopolskaya, but since 1808 it had mostly been referred to by its modern name. The origin of the name is unclear, though it may be related to that of Ustyug.