Karelia can refer to
- Historical province Karelia - a historical province of Sweden (Historical provinces of Finland)
- Northern Karelia - an administrative region in Finland
- Southern Karelia - an administrative region in Finland
- Republic of Karelia - an autonomous republic in Russia (Eastern Karelia)
- Karelo-Finnish SSR - a Soviet Republic (1940-1956)
- Karelian language - a Finno-Ugric language
- Karelia Suite of classical music by Jean Sibelius
- Karelia Software, LLC - software company with a headquarters in Alameda, California, that claims to pioneer the desktop web application market.