Spas-Demensk (Russian: Спас-Де́менск) is a town and the administrative center of Spas-Demensky District of Kaluga Oblast, Russia, located on the Demena River (an arm of the Ugra) 197 kilometers (122 mi) west of Kaluga. Population: 4,896 (2010 Census); 5,296 (2002 Census); 6,239 (1989 Census).