Karlskrona is a locality and the seat of Karlskrona Municipality, Blekinge County, Sweden with a population of 66,675 in 2018. It is also the capital of Blekinge County. Karlskrona is known as Sweden's only baroque city and is host to Sweden's largest naval base and the headquarters of the Swedish Coast Guard.

Karlskrona Municipality is a municipality in Blekinge County in South Sweden in southern Sweden. It borders to Emmaboda Municipality, Torsås Municipality and Ronneby Municipality. The city of Karlskrona is the seat of the municipality.