Spas-Demensk is a town located in Russia that serves as the administrative center of the Spas-Demensky District. It is situated on the Demena River, approximately 197 kilometers (122 miles) west of Kaluga, which is the administrative center of the Kaluga Oblast.
The population of the town has seen a gradual decline over recent decades. According to census data, the population was 6,239 in the 1989 Soviet census, decreasing to 5,296 in 2002, 4,896 in 2010, and reaching 4,569 by the 2021 census.