Kalmar County (Kalmar län) is a county or län in southern Sweden. It borders the counties of Kronoberg, Jönköping, Blekinge and Östergötland. To the east in the Baltic Sea is the island Gotland.

The counties are mainly administrative units. Geographically Kalmar County covers the eastern part in the Småland province, and the entire island of Öland. For the areas history and culture, see those areas.