The 4th Naval Warfare Flotilla ( or 4. sjöstridsflj) is Swedish Navy flotilla located in the county of Stockholm, active since 1994. The flotilla is located at Haninge Garrison and shares its location with the 1st Marine Regiment.
The flotilla was established on 1 July 1994 as the 2nd Mine Warfare Section, following the Coastal Fleet's decision to consolidate minelayers and minesweepers into a single unit.
Following the changes introduced by the Swedish Government in the Defence Act of 2004, the flotilla was reorganized into a multi-purpose unit rather than being solely focused on mine warfare.
As of 2024, the peacetime organization of the 4th Naval Warfare Flotilla is as follows: