K
- Kaiser: 7,600 ton Kaiser class armored frigate, launched 1874
- Kaiser: 25,000 ton Kaiser class battleship, launched 1911
- Kaiser Barbarossa: 11,600 ton Kaiser Friedrich III class battleship, launched 1900
- Kaiser Friedrich III: 11,600 ton Kaiser Friedrich III class battleship, launched 1896
- Kaiser Karl der Große: 11,600 ton Kaiser Friedrich III class battleship, launched 1899
- Kaiser Wilhelm II: 11,600 ton Kaiser Friedrich III class battleship, launched 1897
- Kaiser Wilhelm der Große: 11,600 ton Kaiser Friedrich III class battleship, launched 1899
- Kaiserin: 25,000 ton Kaiser class battleship, launched 1911
- Kaiserin Augusta: 6,000 ton unique heavy cruiser, launched 1892
- Kamerun, Norwegian minesweeper Rauma captured in April 1940, re-designated as Vorpostenboot, later to minelayer.
- Karl Galster: 2,400 ton Type 1936 destroyer
- Karlsruhe: Karlsruhe class light cruiser, launched 1912
- Karlsruhe: Königsberg class light cruiser, launched 1915
- Karlsruhe: 7,200 ton Königsberg class light cruiser, launched 1927
- Karlsruhe: Bremen class (Type 122) frigate
- Karpfen: Barbe class (Type 520) utility landing craft, used as transport ships (decommissioned)
- Koblenz: Lindau class (Type 320) minesweeper, commissioned 1958 to 1975, upgraded to Type 331
- Koblenz: Fulda class (Type 331, upgraded Type 320 Lindau class) minesweepers, commissioned 1978 to 1999
- Kolberg: 4,400 ton Kolberg class light cruiser, launched 1908
- Köln: 7,200 ton Königsberg class light cruiser, launched 1928
- Köln: Köln class (Type 120) frigate, commissioned 1961 to 1982
- Köln: Bremen class (Type 122) frigate
- Komet HSK 7: 7,500 ton unique auxiliary merchant cruiser
- Kondor: Seeadler (Type 141) fast attack craft, commissioned 1959 to 1976
- Kondor: Albatross class (Type 143) fast attack craft, decommissioned
- König: 26,000 ton König class battleship, launched 1913
- König Albert: 25,000 ton Kaiser class battleship, launched 1912
- König Wilhelm: unique amoured frigate, 9,700 tons, launched 1868; rebuilt 1897 into heavy cruiser
- Königsberg: Königsberg class light cruiser, launched 1905
- Königsberg: Königsberg class light cruiser, launched 1915
- Königsberg: 7,200 ton Königsberg class light cruiser, launched 1925
- Konstanz: Lindau class (Type 320) minesweeper, commissioned 1959 to 1980, upgraded to Type 351 and recommissioned 1989 to 2000
- Kormoran HSK 8: 19,000 ton unique auxiliary merchant cruiser
- Kormoran: Seeadler (Type 141) fast attack craft, commissioned 1959 to 1976
- Kormoran: Albatross class (Type 143) fast attack craft, decommissioned
- Kranich: Jaguar (Type 140) fast attack craft, commissioned 1959—1973
- Kranich: Tiger class (Type 148) fast attack craft, decommissioned
- Krebs: Krebs class (Type 340) minesweeper, commissioned 1959 to 1973
- Kronprinz: Original name for 1914 battleship Kronprinz Wilhelm
- Kronprinz Wilhelm: 26,000 ton König class battleship, renamed from Kronprinz in 1918
- Kronprinz Wilhelm: 24,900 ton auxiliary cruiser, built as a civilian liner in 1901, commissioned as an auxiliary cruiser in 1914, surrendered to the US in 1915
- Kulmbach: Kulmbach class (Type 332) minehunter
- Kurfürst Friedrich Wilhelm: 10,500 ton Brandenburg class battleship, launched 1891
Read more about this topic: List Of Naval Ships Of Germany