F
- Fei Ying (China): 850-ton destroyer
- Flora (Denmark): 369-ton C class submarine
- Freja (Denmark): 322-ton patrol boat, became Sudpol (Germany), then Freya (Germany)
- Fresia (Chile): 435-ton submarine
- Frøya (Norway): 870-ton minelayer
- Fu Yu (China): 630-ton gunboat
Read more about this topic: List Of World War II Ships Of Less Than 1000 Tons