The 4th Naval Warfare Flotilla (Swedish: Fjärde sjöstridsflottiljen or 4. sjöstridsflj) is one of three flotillas in the Swedish Navy and is a part of the Berga Naval Base.

The unit is based at Berga south of the Swedish capital Stockholm.

It was formed in 2005 when the former naval mine warfare flotilla was split and surface warfare units were added.

The flotilla is split into four different divisions as of 2005.

41st Corvette Division (41:a korvettdivisionen) 42nd Minesweeper Division (42:a minröjningsdivisionen) 43rd Support Division (43:e underhållsdivisionen) 44th Mine Clearance Division (44:e röjdykardivisionen)